File: //usr/lib/ruby/gems/3.2.0/gems/rbs-2.8.2/core/string.rbs
# <!-- rdoc-file=string.c -->
# A String object has an arbitrary sequence of bytes, typically representing
# text or binary data. A String object may be created using String::new or as
# literals.
#
# String objects differ from Symbol objects in that Symbol objects are designed
# to be used as identifiers, instead of text or data.
#
# You can create a String object explicitly with:
#
# * A [string literal](doc/syntax/literals_rdoc.html#label-String+Literals).
# * A [heredoc
# literal](doc/syntax/literals_rdoc.html#label-Here+Document+Literals).
#
#
# You can convert certain objects to Strings with:
#
# * Method [String](Kernel.html#method-i-String).
#
#
# Some String methods modify `self`. Typically, a method whose name ends with
# `!` modifies `self` and returns `self`; often a similarly named method
# (without the `!`) returns a new string.
#
# In general, if there exist both bang and non-bang version of method, the bang!
# mutates and the non-bang! does not. However, a method without a bang can also
# mutate, such as String#replace.
#
# ## Substitution Methods
#
# These methods perform substitutions:
#
# * String#sub: One substitution (or none); returns a new string.
# * String#sub!: One substitution (or none); returns `self`.
# * String#gsub: Zero or more substitutions; returns a new string.
# * String#gsub!: Zero or more substitutions; returns `self`.
#
#
# Each of these methods takes:
#
# * A first argument, `pattern` (string or regexp), that specifies the
# substring(s) to be replaced.
#
# * Either of these:
#
# * A second argument, `replacement` (string or hash), that determines the
# replacing string.
# * A block that will determine the replacing string.
#
#
#
# The examples in this section mostly use methods String#sub and String#gsub;
# the principles illustrated apply to all four substitution methods.
#
# **Argument `pattern`**
#
# Argument `pattern` is commonly a regular expression:
#
# s = 'hello'
# s.sub(/[aeiou]/, '*') # => "h*llo"
# s.gsub(/[aeiou]/, '*') # => "h*ll*"
# s.gsub(/[aeiou]/, '') # => "hll"
# s.sub(/ell/, 'al') # => "halo"
# s.gsub(/xyzzy/, '*') # => "hello"
# 'THX1138'.gsub(/\d+/, '00') # => "THX00"
#
# When `pattern` is a string, all its characters are treated as ordinary
# characters (not as regexp special characters):
#
# 'THX1138'.gsub('\d+', '00') # => "THX1138"
#
# **\String `replacement`**
#
# If `replacement` is a string, that string will determine the replacing string
# that is to be substituted for the matched text.
#
# Each of the examples above uses a simple string as the replacing string.
#
# String `replacement` may contain back-references to the pattern's captures:
#
# * `\n` (*n* a non-negative integer) refers to `$n`.
# * `\k<name>` refers to the named capture `name`.
#
#
# See regexp.rdoc for details.
#
# Note that within the string `replacement`, a character combination such as
# `$&` is treated as ordinary text, and not as a special match variable.
# However, you may refer to some special match variables using these
# combinations:
#
# * `\&` and `\0` correspond to `$&`, which contains the complete matched
# text.
# * `\'` corresponds to `$'`, which contains string after match.
# * `\`` corresponds to `$``, which contains string before match.
# * `+` corresponds to `$+`, which contains last capture group.
#
#
# See regexp.rdoc for details.
#
# Note that `\\\` is interpreted as an escape, i.e., a single backslash.
#
# Note also that a string literal consumes backslashes. See [String
# Literals](doc/syntax/literals_rdoc.html#label-String+Literals) for details
# about string literals.
#
# A back-reference is typically preceded by an additional backslash. For
# example, if you want to write a back-reference `\&` in `replacement` with a
# double-quoted string literal, you need to write `"..\\\\&.."`.
#
# If you want to write a non-back-reference string `\&` in `replacement`, you
# need first to escape the backslash to prevent this method from interpreting it
# as a back-reference, and then you need to escape the backslashes again to
# prevent a string literal from consuming them: `"..\\\\\\\\&.."`.
#
# You may want to use the block form to avoid a lot of backslashes.
#
# **\Hash `replacement`**
#
# If argument `replacement` is a hash, and `pattern` matches one of its keys,
# the replacing string is the value for that key:
#
# h = {'foo' => 'bar', 'baz' => 'bat'}
# 'food'.sub('foo', h) # => "bard"
#
# Note that a symbol key does not match:
#
# h = {foo: 'bar', baz: 'bat'}
# 'food'.sub('foo', h) # => "d"
#
# **Block**
#
# In the block form, the current match string is passed to the block; the
# block's return value becomes the replacing string:
#
# s = '@'
# '1234'.gsub(/\d/) {|match| s.succ! } # => "ABCD"
#
# Special match variables such as `$1`, `$2`, `$``, `$&`, and `$'` are set
# appropriately.
#
# ## What's Here
#
# First, what's elsewhere. Class String:
#
# * Inherits from [class
# Object](Object.html#class-Object-label-What-27s+Here).
# * Includes [module
# Comparable](Comparable.html#module-Comparable-label-What-27s+Here).
#
#
# Here, class String provides methods that are useful for:
#
# * [Creating a String](#class-String-label-Methods+for+Creating+a+String)
# * [Frozen/Unfrozen
# Strings](#class-String-label-Methods+for+a+Frozen-2FUnfrozen+String)
# * [Querying](#class-String-label-Methods+for+Querying)
# * [Comparing](#class-String-label-Methods+for+Comparing)
# * [Modifying a String](#class-String-label-Methods+for+Modifying+a+String)
# * [Converting to New
# String](#class-String-label-Methods+for+Converting+to+New+String)
# * [Converting to
# Non-String](#class-String-label-Methods+for+Converting+to+Non--5CString)
# * [Iterating](#class-String-label-Methods+for+Iterating)
#
#
# ### Methods for Creating a String
#
# ::new
# : Returns a new string.
#
# ::try_convert
# : Returns a new string created from a given object.
#
#
#
# ### Methods for a Frozen/Unfrozen String
#
# [#+string](#method-i-2B-40)
# : Returns a string that is not frozen: `self`, if not frozen; `self.dup`
# otherwise.
#
# [#-string](#method-i-2D-40)
# : Returns a string that is frozen: `self`, if already frozen;
# `self.freeze` otherwise.
#
# #freeze
# : Freezes `self`, if not already frozen; returns `self`.
#
#
#
# ### Methods for Querying
#
# *Counts*
#
# #length, #size
# : Returns the count of characters (not bytes).
#
# #empty?
# : Returns `true` if `self.length` is zero; `false` otherwise.
#
# #bytesize
# : Returns the count of bytes.
#
# #count
# : Returns the count of substrings matching given strings.
#
#
#
# *Substrings*
#
# [#=~](#method-i-3D~)
# : Returns the index of the first substring that matches a given Regexp
# or other object; returns `nil` if no match is found.
#
# #index
# : Returns the index of the *first* occurrence of a given substring;
# returns `nil` if none found.
#
# #rindex
# : Returns the index of the *last* occurrence of a given substring;
# returns `nil` if none found.
#
# #include?
# : Returns `true` if the string contains a given substring; `false`
# otherwise.
#
# #match
# : Returns a MatchData object if the string matches a given Regexp; `nil`
# otherwise.
#
# #match?
# : Returns `true` if the string matches a given Regexp; `false`
# otherwise.
#
# #start_with?
# : Returns `true` if the string begins with any of the given substrings.
#
# #end_with?
# : Returns `true` if the string ends with any of the given substrings.
#
#
#
# *Encodings*
#
# #encoding
# : Returns the Encoding object that represents the encoding of the
# string.
#
# #unicode_normalized?
# : Returns `true` if the string is in Unicode normalized form; `false`
# otherwise.
#
# #valid_encoding?
# : Returns `true` if the string contains only characters that are valid
# for its encoding.
#
# #ascii_only?
# : Returns `true` if the string has only ASCII characters; `false`
# otherwise.
#
#
#
# *Other*
#
# #sum
# : Returns a basic checksum for the string: the sum of each byte.
#
# #hash
# : Returns the integer hash code.
#
#
#
# ### Methods for Comparing
#
# [#==, #===](#method-i-3D-3D)
# : Returns `true` if a given other string has the same content as `self`.
#
# #eql?
# : Returns `true` if the content is the same as the given other string.
#
# [#<=>](#method-i-3C-3D-3E)
# : Returns -1, 0, or 1 as a given other string is smaller than, equal to,
# or larger than `self`.
#
# #casecmp
# : Ignoring case, returns -1, 0, or 1 as a given other string is smaller
# than, equal to, or larger than `self`.
#
# #casecmp?
# : Returns `true` if the string is equal to a given string after Unicode
# case folding; `false` otherwise.
#
#
#
# ### Methods for Modifying a String
#
# Each of these methods modifies `self`.
#
# *Insertion*
#
# #insert
# : Returns `self` with a given string inserted at a given offset.
#
# #<<
# : Returns `self` concatenated with a given string or integer.
#
#
#
# *Substitution*
#
# #sub!
# : Replaces the first substring that matches a given pattern with a given
# replacement string; returns `self` if any changes, `nil` otherwise.
#
# #gsub!
# : Replaces each substring that matches a given pattern with a given
# replacement string; returns `self` if any changes, `nil` otherwise.
#
# #succ!, #next!
# : Returns `self` modified to become its own successor.
#
# #replace
# : Returns `self` with its entire content replaced by a given string.
#
# #reverse!
# : Returns `self` with its characters in reverse order.
#
# #setbyte
# : Sets the byte at a given integer offset to a given value; returns the
# argument.
#
# #tr!
# : Replaces specified characters in `self` with specified replacement
# characters; returns `self` if any changes, `nil` otherwise.
#
# #tr_s!
# : Replaces specified characters in `self` with specified replacement
# characters, removing duplicates from the substrings that were
# modified; returns `self` if any changes, `nil` otherwise.
#
#
#
# *Casing*
#
# #capitalize!
# : Upcases the initial character and downcases all others; returns `self`
# if any changes, `nil` otherwise.
#
# #downcase!
# : Downcases all characters; returns `self` if any changes, `nil`
# otherwise.
#
# #upcase!
# : Upcases all characters; returns `self` if any changes, `nil`
# otherwise.
#
# #swapcase!
# : Upcases each downcase character and downcases each upcase character;
# returns `self` if any changes, `nil` otherwise.
#
#
#
# *Encoding*
#
# #encode!
# : Returns `self` with all characters transcoded from one given encoding
# into another.
#
# #unicode_normalize!
# : Unicode-normalizes `self`; returns `self`.
#
# #scrub!
# : Replaces each invalid byte with a given character; returns `self`.
#
# #force_encoding
# : Changes the encoding to a given encoding; returns `self`.
#
#
#
# *Deletion*
#
# #clear
# : Removes all content, so that `self` is empty; returns `self`.
#
# #slice!, #[]=
# : Removes a substring determined by a given index, start/length, range,
# regexp, or substring.
#
# #squeeze!
# : Removes contiguous duplicate characters; returns `self`.
#
# #delete!
# : Removes characters as determined by the intersection of substring
# arguments.
#
# #lstrip!
# : Removes leading whitespace; returns `self` if any changes, `nil`
# otherwise.
#
# #rstrip!
# : Removes trailing whitespace; returns `self` if any changes, `nil`
# otherwise.
#
# #strip!
# : Removes leading and trailing whitespace; returns `self` if any
# changes, `nil` otherwise.
#
# #chomp!
# : Removes trailing record separator, if found; returns `self` if any
# changes, `nil` otherwise.
#
# #chop!
# : Removes trailing whitespace if found, otherwise removes the last
# character; returns `self` if any changes, `nil` otherwise.
#
#
#
# ### Methods for Converting to New String
#
# Each of these methods returns a new String based on `self`, often just a
# modified copy of `self`.
#
# *Extension*
#
# #*
# : Returns the concatenation of multiple copies of `self`,
#
# #+
# : Returns the concatenation of `self` and a given other string.
#
# #center
# : Returns a copy of `self` centered between pad substring.
#
# #concat
# : Returns the concatenation of `self` with given other strings.
#
# #prepend
# : Returns the concatenation of a given other string with `self`.
#
# #ljust
# : Returns a copy of `self` of a given length, right-padded with a given
# other string.
#
# #rjust
# : Returns a copy of `self` of a given length, left-padded with a given
# other string.
#
#
#
# *Encoding*
#
# #b
# : Returns a copy of `self` with ASCII-8BIT encoding.
#
# #scrub
# : Returns a copy of `self` with each invalid byte replaced with a given
# character.
#
# #unicode_normalize
# : Returns a copy of `self` with each character Unicode-normalized.
#
# #encode
# : Returns a copy of `self` with all characters transcoded from one given
# encoding into another.
#
#
#
# *Substitution*
#
# #dump
# : Returns a copy of +self with all non-printing characters replaced by
# xHH notation and all special characters escaped.
#
# #undump
# : Returns a copy of +self with all `\xNN` notation replace by `\uNNNN`
# notation and all escaped characters unescaped.
#
# #sub
# : Returns a copy of `self` with the first substring matching a given
# pattern replaced with a given replacement string;.
#
# #gsub
# : Returns a copy of `self` with each substring that matches a given
# pattern replaced with a given replacement string.
#
# #succ, #next
# : Returns the string that is the successor to `self`.
#
# #reverse
# : Returns a copy of `self` with its characters in reverse order.
#
# #tr
# : Returns a copy of `self` with specified characters replaced with
# specified replacement characters.
#
# #tr_s
# : Returns a copy of `self` with specified characters replaced with
# specified replacement characters, removing duplicates from the
# substrings that were modified.
#
# #%
# : Returns the string resulting from formatting a given object into
# `self`
#
#
#
# *Casing*
#
# #capitalize
# : Returns a copy of `self` with the first character upcased and all
# other characters downcased.
#
# #downcase
# : Returns a copy of `self` with all characters downcased.
#
# #upcase
# : Returns a copy of `self` with all characters upcased.
#
# #swapcase
# : Returns a copy of `self` with all upcase characters downcased and all
# downcase characters upcased.
#
#
#
# *Deletion*
#
# #delete
# : Returns a copy of `self` with characters removed
#
# #delete_prefix
# : Returns a copy of `self` with a given prefix removed.
#
# #delete_suffix
# : Returns a copy of `self` with a given suffix removed.
#
# #lstrip
# : Returns a copy of `self` with leading whitespace removed.
#
# #rstrip
# : Returns a copy of `self` with trailing whitespace removed.
#
# #strip
# : Returns a copy of `self` with leading and trailing whitespace removed.
#
# #chomp
# : Returns a copy of `self` with a trailing record separator removed, if
# found.
#
# #chop
# : Returns a copy of `self` with trailing whitespace or the last
# character removed.
#
# #squeeze
# : Returns a copy of `self` with contiguous duplicate characters removed.
#
# #[], #slice
# : Returns a substring determined by a given index, start/length, or
# range, or string.
#
# #byteslice
# : Returns a substring determined by a given index, start/length, or
# range.
#
# #chr
# : Returns the first character.
#
#
#
# *Duplication*
#
# #to_s, $to_str
# : If `self` is a subclass of String, returns `self` copied into a
# String; otherwise, returns `self`.
#
#
#
# ### Methods for Converting to Non-String
#
# Each of these methods converts the contents of `self` to a non-String.
#
# *Characters, Bytes, and Clusters*
#
# #bytes
# : Returns an array of the bytes in `self`.
#
# #chars
# : Returns an array of the characters in `self`.
#
# #codepoints
# : Returns an array of the integer ordinals in `self`.
#
# #getbyte
# : Returns an integer byte as determined by a given index.
#
# #grapheme_clusters
# : Returns an array of the grapheme clusters in `self`.
#
#
#
# *Splitting*
#
# #lines
# : Returns an array of the lines in `self`, as determined by a given
# record separator.
#
# #partition
# : Returns a 3-element array determined by the first substring that
# matches a given substring or regexp,
#
# #rpartition
# : Returns a 3-element array determined by the last substring that
# matches a given substring or regexp,
#
# #split
# : Returns an array of substrings determined by a given delimiter --
# regexp or string -- or, if a block given, passes those substrings to
# the block.
#
#
#
# *Matching*
#
# #scan
# : Returns an array of substrings matching a given regexp or string, or,
# if a block given, passes each matching substring to the block.
#
# #unpack
# : Returns an array of substrings extracted from `self` according to a
# given format.
#
# #unpack1
# : Returns the first substring extracted from `self` according to a given
# format.
#
#
#
# *Numerics*
#
# #hex
# : Returns the integer value of the leading characters, interpreted as
# hexadecimal digits.
#
# #oct
# : Returns the integer value of the leading characters, interpreted as
# octal digits.
#
# #ord
# : Returns the integer ordinal of the first character in `self`.
#
# #to_i
# : Returns the integer value of leading characters, interpreted as an
# integer.
#
# #to_f
# : Returns the floating-point value of leading characters, interpreted as
# a floating-point number.
#
#
#
# *Strings and Symbols*
#
# #inspect
# : Returns copy of `self`, enclosed in double-quotes, with special
# characters escaped.
#
# #to_sym, #intern
# : Returns the symbol corresponding to `self`.
#
#
#
# ### Methods for Iterating
#
# #each_byte
# : Calls the given block with each successive byte in `self`.
#
# #each_char
# : Calls the given block with each successive character in `self`.
#
# #each_codepoint
# : Calls the given block with each successive integer codepoint in
# `self`.
#
# #each_grapheme_cluster
# : Calls the given block with each successive grapheme cluster in `self`.
#
# #each_line
# : Calls the given block with each successive line in `self`, as
# determined by a given record separator.
#
# #upto
# : Calls the given block with each string value returned by successive
# calls to #succ.
#
class String
include Comparable
# <!--
# rdoc-file=string.c
# - String.try_convert(object) -> object, new_string, or nil
# -->
# If `object` is a String object, returns `object`.
#
# Otherwise if `object` responds to `:to_str`, calls `object.to_str` and returns
# the result.
#
# Returns `nil` if `object` does not respond to `:to_str`.
#
# Raises an exception unless `object.to_str` returns a String object.
#
def self.try_convert: (untyped obj) -> String?
public
# <!--
# rdoc-file=string.c
# - string % object -> new_string
# -->
# Returns the result of formatting `object` into the format specification `self`
# (see Kernel#sprintf for formatting details):
#
# "%05d" % 123 # => "00123"
#
# If `self` contains multiple substitutions, `object` must be an Array or Hash
# containing the values to be substituted:
#
# "%-5s: %016x" % [ "ID", self.object_id ] # => "ID : 00002b054ec93168"
# "foo = %{foo}" % {foo: 'bar'} # => "foo = bar"
# "foo = %{foo}, baz = %{baz}" % {foo: 'bar', baz: 'bat'} # => "foo = bar, baz = bat"
#
def %: (Hash[Symbol, untyped]) -> String
| (Array[untyped]) -> String
| (untyped arg) -> String
# <!--
# rdoc-file=string.c
# - string * integer -> new_string
# -->
# Returns a new String containing `integer` copies of `self`:
#
# "Ho! " * 3 # => "Ho! Ho! Ho! "
# "Ho! " * 0 # => ""
#
def *: (int n) -> String
# <!--
# rdoc-file=string.c
# - string + other_string -> new_string
# -->
# Returns a new String containing `other_string` concatenated to `self`:
#
# "Hello from " + self.to_s # => "Hello from main"
#
def +: (string other_str) -> String
# <!--
# rdoc-file=string.c
# - +string -> new_string or self
# -->
# Returns `self` if `self` is not frozen.
#
# Otherwise. returns `self.dup`, which is not frozen.
#
def +@: () -> String
# <!--
# rdoc-file=string.c
# - -string -> frozen_string
# -->
# Returns a frozen, possibly pre-existing copy of the string.
#
# The returned String will be deduplicated as long as it does not have any
# instance variables set on it.
#
def -@: () -> String
# <!--
# rdoc-file=string.c
# - string << object -> string
# -->
# Concatenates `object` to `self` and returns `self`:
#
# s = 'foo'
# s << 'bar' # => "foobar"
# s # => "foobar"
#
# If `object` is an Integer, the value is considered a codepoint and converted
# to a character before concatenation:
#
# s = 'foo'
# s << 33 # => "foo!"
#
# Related: String#concat, which takes multiple arguments.
#
def <<: (string | Integer str_or_codepoint) -> String
# <!--
# rdoc-file=string.c
# - string <=> other_string -> -1, 0, 1, or nil
# -->
# Compares `self` and `other_string`, returning:
#
# * -1 if `other_string` is larger.
# * 0 if the two are equal.
# * 1 if `other_string` is smaller.
# * `nil` if the two are incomparable.
#
#
# Examples:
#
# 'foo' <=> 'foo' # => 0
# 'foo' <=> 'food' # => -1
# 'food' <=> 'foo' # => 1
# 'FOO' <=> 'foo' # => -1
# 'foo' <=> 'FOO' # => 1
# 'foo' <=> 1 # => nil
#
def <=>: (string other) -> Integer
| (untyped other) -> Integer?
# <!--
# rdoc-file=string.c
# - string == object -> true or false
# - string === object -> true or false
# -->
# Returns `true` if `object` has the same length and content; as `self`; `false`
# otherwise:
#
# s = 'foo'
# s == 'foo' # => true
# s == 'food' # => false
# s == 'FOO' # => false
#
# Returns `false` if the two strings' encodings are not compatible:
# "\u{e4 f6 fc}".encode("ISO-8859-1") == ("\u{c4 d6 dc}") # => false
#
# If `object` is not an instance of String but responds to `to_str`, then the
# two strings are compared using `object.==`.
#
def ==: (untyped obj) -> bool
# <!-- rdoc-file=string.c -->
# Returns `true` if `object` has the same length and content; as `self`; `false`
# otherwise:
#
# s = 'foo'
# s == 'foo' # => true
# s == 'food' # => false
# s == 'FOO' # => false
#
# Returns `false` if the two strings' encodings are not compatible:
# "\u{e4 f6 fc}".encode("ISO-8859-1") == ("\u{c4 d6 dc}") # => false
#
# If `object` is not an instance of String but responds to `to_str`, then the
# two strings are compared using `object.==`.
#
def ===: (untyped obj) -> bool
# <!--
# rdoc-file=string.c
# - string =~ regexp -> integer or nil
# - string =~ object -> integer or nil
# -->
# Returns the Integer index of the first substring that matches the given
# `regexp`, or `nil` if no match found:
#
# 'foo' =~ /f/ # => 0
# 'foo' =~ /o/ # => 1
# 'foo' =~ /x/ # => nil
#
# Note: also updates [Regexp-related global
# variables](Regexp.html#class-Regexp-label-Special+global+variables).
#
# If the given `object` is not a Regexp, returns the value returned by `object
# =~ self`.
#
# Note that `string =~ regexp` is different from `regexp =~ string` (see
# [Regexp#=~](https://ruby-doc.org/core-2.7.1/Regexp.html#method-i-3D-7E)):
#
# number= nil
# "no. 9" =~ /(?<number>\d+)/
# number # => nil (not assigned)
# /(?<number>\d+)/ =~ "no. 9"
# number #=> "9"
#
def =~: (untyped obj) -> Integer?
# <!--
# rdoc-file=string.c
# - string[index] -> new_string or nil
# - string[start, length] -> new_string or nil
# - string[range] -> new_string or nil
# - string[regexp, capture = 0] -> new_string or nil
# - string[substring] -> new_string or nil
# -->
# Returns the substring of `self` specified by the arguments.
#
# When the single Integer argument `index` is given, returns the 1-character
# substring found in `self` at offset `index`:
#
# 'bar'[2] # => "r"
#
# Counts backward from the end of `self` if `index` is negative:
#
# 'foo'[-3] # => "f"
#
# Returns `nil` if `index` is out of range:
#
# 'foo'[3] # => nil
# 'foo'[-4] # => nil
#
# When the two Integer arguments `start` and `length` are given, returns the
# substring of the given `length` found in `self` at offset `start`:
#
# 'foo'[0, 2] # => "fo"
# 'foo'[0, 0] # => ""
#
# Counts backward from the end of `self` if `start` is negative:
#
# 'foo'[-2, 2] # => "oo"
#
# Special case: returns a new empty String if `start` is equal to the length of
# `self`:
#
# 'foo'[3, 2] # => ""
#
# Returns `nil` if `start` is out of range:
#
# 'foo'[4, 2] # => nil
# 'foo'[-4, 2] # => nil
#
# Returns the trailing substring of `self` if `length` is large:
#
# 'foo'[1, 50] # => "oo"
#
# Returns `nil` if `length` is negative:
#
# 'foo'[0, -1] # => nil
#
# When the single Range argument `range` is given, derives `start` and `length`
# values from the given `range`, and returns values as above:
#
# * `'foo'[0..1]` is equivalent to `'foo'[0, 2]`.
# * `'foo'[0...1]` is equivalent to `'foo'[0, 1]`.
#
#
# When the Regexp argument `regexp` is given, and the `capture` argument is `0`,
# returns the first matching substring found in `self`, or `nil` if none found:
#
# 'foo'[/o/] # => "o"
# 'foo'[/x/] # => nil
# s = 'hello there'
# s[/[aeiou](.)\1/] # => "ell"
# s[/[aeiou](.)\1/, 0] # => "ell"
#
# If argument `capture` is given and not `0`, it should be either an Integer
# capture group index or a String or Symbol capture group name; the method call
# returns only the specified capture (see [Regexp
# Capturing](Regexp.html#class-Regexp-label-Capturing)):
#
# s = 'hello there'
# s[/[aeiou](.)\1/, 1] # => "l"
# s[/(?<vowel>[aeiou])(?<non_vowel>[^aeiou])/, "non_vowel"] # => "l"
# s[/(?<vowel>[aeiou])(?<non_vowel>[^aeiou])/, :vowel] # => "e"
#
# If an invalid capture group index is given, `nil` is returned. If an invalid
# capture group name is given, `IndexError` is raised.
#
# When the single String argument `substring` is given, returns the substring
# from `self` if found, otherwise `nil`:
#
# 'foo'['oo'] # => "oo"
# 'foo'['xx'] # => nil
#
# String#slice is an alias for String#[].
#
def []: (int index) -> String?
| (int start, int length) -> String?
| (Range[Integer] | Range[Integer?] range) -> String?
| (Regexp regexp) -> String?
| (Regexp regexp, int | String capture) -> String?
| (String match_str) -> String?
# <!--
# rdoc-file=string.c
# - str[integer] = new_str
# - str[integer, integer] = new_str
# - str[range] = aString
# - str[regexp] = new_str
# - str[regexp, integer] = new_str
# - str[regexp, name] = new_str
# - str[other_str] = new_str
# -->
# Element Assignment---Replaces some or all of the content of *str*. The portion
# of the string affected is determined using the same criteria as String#[]. If
# the replacement string is not the same length as the text it is replacing, the
# string will be adjusted accordingly. If the regular expression or string is
# used as the index doesn't match a position in the string, IndexError is
# raised. If the regular expression form is used, the optional second Integer
# allows you to specify which portion of the match to replace (effectively using
# the MatchData indexing rules. The forms that take an Integer will raise an
# IndexError if the value is out of range; the Range form will raise a
# RangeError, and the Regexp and String will raise an IndexError on negative
# match.
#
def []=: (int pos, String new_str) -> String
| (int begin_pos, int end_pos, String new_str) -> String
| (Range[Integer] | Range[Integer?] range, String new_str) -> String
| (Regexp regexp, String new_str) -> String
| (Regexp regexp, int capture, String new_str) -> String
| (Regexp regexp, String name, String new_str) -> String
| (String other_str, String new_str) -> String
# <!--
# rdoc-file=string.c
# - str.ascii_only? -> true or false
# -->
# Returns true for a string which has only ASCII characters.
#
# "abc".force_encoding("UTF-8").ascii_only? #=> true
# "abc\u{6666}".force_encoding("UTF-8").ascii_only? #=> false
#
def ascii_only?: () -> bool
# <!--
# rdoc-file=string.c
# - str.b -> str
# -->
# Returns a copied string whose encoding is ASCII-8BIT.
#
def b: () -> String
# <!--
# rdoc-file=string.c
# - str.bytes -> an_array
# -->
# Returns an array of bytes in *str*. This is a shorthand for
# `str.each_byte.to_a`.
#
# If a block is given, which is a deprecated form, works the same as
# `each_byte`.
#
def bytes: () -> Array[Integer]
| () { (Integer byte) -> void } -> String
# <!--
# rdoc-file=string.c
# - bytesize -> integer
# -->
# Returns the count of bytes in `self`:
#
# "\x80\u3042".bytesize # => 4
# "hello".bytesize # => 5
#
# Related: String#length.
#
def bytesize: () -> Integer
# <!--
# rdoc-file=string.c
# - byteslice(index, length = 1) -> string or nil
# - byteslice(range) -> string or nil
# -->
# Returns a substring of `self`, or `nil` if the substring cannot be
# constructed.
#
# With integer arguments `index` and `length` given, returns the substring
# beginning at the given `index` of the given `length` (if possible), or `nil`
# if `length` is negative or `index` falls outside of `self`:
#
# s = '0123456789' # => "0123456789"
# s.byteslice(2) # => "2"
# s.byteslice(200) # => nil
# s.byteslice(4, 3) # => "456"
# s.byteslice(4, 30) # => "456789"
# s.byteslice(4, -1) # => nil
# s.byteslice(40, 2) # => nil
#
# In either case above, counts backwards from the end of `self` if `index` is
# negative:
#
# s = '0123456789' # => "0123456789"
# s.byteslice(-4) # => "6"
# s.byteslice(-4, 3) # => "678"
#
# With Range argument `range` given, returns `byteslice(range.begin,
# range.size)`:
#
# s = '0123456789' # => "0123456789"
# s.byteslice(4..6) # => "456"
# s.byteslice(-6..-4) # => "456"
# s.byteslice(5..2) # => "" # range.size is zero.
# s.byteslice(40..42) # => nil
#
# In all cases, a returned string has the same encoding as `self`:
#
# s.encoding # => #<Encoding:UTF-8>
# s.byteslice(4).encoding # => #<Encoding:UTF-8>
#
def byteslice: (int start, ?int length) -> String?
| (Range[Integer] | Range[Integer?] range) -> String?
# <!--
# rdoc-file=string.c
# - capitalize(*options) -> string
# -->
# Returns a string containing the characters in `self`; the first character is
# upcased; the remaining characters are downcased:
#
# s = 'hello World!' # => "hello World!"
# s.capitalize # => "Hello world!"
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#capitalize!.
#
def capitalize: () -> String
| (:ascii | :lithuanian | :turkic) -> String
| (:lithuanian, :turkic) -> String
| (:turkic, :lithuanian) -> String
# <!--
# rdoc-file=string.c
# - capitalize!(*options) -> self or nil
# -->
# Upcases the first character in `self`; downcases the remaining characters;
# returns `self` if any changes were made, `nil` otherwise:
#
# s = 'hello World!' # => "hello World!"
# s.capitalize! # => "Hello world!"
# s # => "Hello world!"
# s.capitalize! # => nil
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#capitalize.
#
def capitalize!: () -> String?
| (:ascii | :lithuanian | :turkic) -> String?
| (:lithuanian, :turkic) -> String?
| (:turkic, :lithuanian) -> String?
# <!--
# rdoc-file=string.c
# - casecmp(other_string) -> -1, 0, 1, or nil
# -->
# Compares `self.downcase` and `other_string.downcase`; returns:
#
# * -1 if `other_string.downcase` is larger.
# * 0 if the two are equal.
# * 1 if `other_string.downcase` is smaller.
# * `nil` if the two are incomparable.
#
#
# Examples:
#
# 'foo'.casecmp('foo') # => 0
# 'foo'.casecmp('food') # => -1
# 'food'.casecmp('foo') # => 1
# 'FOO'.casecmp('foo') # => 0
# 'foo'.casecmp('FOO') # => 0
# 'foo'.casecmp(1) # => nil
#
# See [Case Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#casecmp?.
#
def casecmp: (untyped other) -> Integer?
# <!--
# rdoc-file=string.c
# - casecmp?(other_string) -> true, false, or nil
# -->
# Returns `true` if `self` and `other_string` are equal after Unicode case
# folding, otherwise `false`:
#
# 'foo'.casecmp?('foo') # => true
# 'foo'.casecmp?('food') # => false
# 'food'.casecmp?('foo') # => false
# 'FOO'.casecmp?('foo') # => true
# 'foo'.casecmp?('FOO') # => true
#
# Returns `nil` if the two values are incomparable:
#
# 'foo'.casecmp?(1) # => nil
#
# See [Case Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#casecmp.
#
def casecmp?: (untyped other) -> bool?
# <!--
# rdoc-file=string.c
# - str.center(width, padstr=' ') -> new_str
# -->
# Centers `str` in `width`. If `width` is greater than the length of `str`,
# returns a new String of length `width` with `str` centered and padded with
# `padstr`; otherwise, returns `str`.
#
# "hello".center(4) #=> "hello"
# "hello".center(20) #=> " hello "
# "hello".center(20, '123') #=> "1231231hello12312312"
#
def center: (int width, ?string padstr) -> String
# <!--
# rdoc-file=string.c
# - str.chars -> an_array
# -->
# Returns an array of characters in *str*. This is a shorthand for
# `str.each_char.to_a`.
#
# If a block is given, which is a deprecated form, works the same as
# `each_char`.
#
def chars: () -> Array[String]
| () { (String char) -> void } -> String
# <!--
# rdoc-file=string.c
# - str.chomp(separator=$/) -> new_str
# -->
# Returns a new String with the given record separator removed from the end of
# *str* (if present). If `$/` has not been changed from the default Ruby record
# separator, then `chomp` also removes carriage return characters (that is, it
# will remove `\n`, `\r`, and `\r\n`). If `$/` is an empty string, it will
# remove all trailing newlines from the string.
#
# "hello".chomp #=> "hello"
# "hello\n".chomp #=> "hello"
# "hello\r\n".chomp #=> "hello"
# "hello\n\r".chomp #=> "hello\n"
# "hello\r".chomp #=> "hello"
# "hello \n there".chomp #=> "hello \n there"
# "hello".chomp("llo") #=> "he"
# "hello\r\n\r\n".chomp('') #=> "hello"
# "hello\r\n\r\r\n".chomp('') #=> "hello\r\n\r"
#
def chomp: (?string separator) -> String
# <!--
# rdoc-file=string.c
# - str.chomp!(separator=$/) -> str or nil
# -->
# Modifies *str* in place as described for String#chomp, returning *str*, or
# `nil` if no modifications were made.
#
def chomp!: (?string separator) -> String?
# <!--
# rdoc-file=string.c
# - str.chop -> new_str
# -->
# Returns a new String with the last character removed. If the string ends with
# `\r\n`, both characters are removed. Applying `chop` to an empty string
# returns an empty string. String#chomp is often a safer alternative, as it
# leaves the string unchanged if it doesn't end in a record separator.
#
# "string\r\n".chop #=> "string"
# "string\n\r".chop #=> "string\n"
# "string\n".chop #=> "string"
# "string".chop #=> "strin"
# "x".chop.chop #=> ""
#
def chop: () -> String
# <!--
# rdoc-file=string.c
# - str.chop! -> str or nil
# -->
# Processes *str* as for String#chop, returning *str*, or `nil` if *str* is the
# empty string. See also String#chomp!.
#
def chop!: () -> String?
# <!--
# rdoc-file=string.c
# - chr -> string
# -->
# Returns a string containing the first character of `self`:
#
# s = 'foo' # => "foo"
# s.chr # => "f"
#
def chr: () -> String
# <!--
# rdoc-file=string.c
# - clear -> self
# -->
# Removes the contents of `self`:
#
# s = 'foo' # => "foo"
# s.clear # => ""
#
def clear: () -> String
# <!--
# rdoc-file=string.c
# - str.codepoints -> an_array
# -->
# Returns an array of the Integer ordinals of the characters in *str*. This is
# a shorthand for `str.each_codepoint.to_a`.
#
# If a block is given, which is a deprecated form, works the same as
# `each_codepoint`.
#
def codepoints: () -> ::Array[Integer]
| () { (Integer codepoint) -> void } -> String
# <!--
# rdoc-file=string.c
# - concat(*objects) -> string
# -->
# Concatenates each object in `objects` to `self` and returns `self`:
#
# s = 'foo'
# s.concat('bar', 'baz') # => "foobarbaz"
# s # => "foobarbaz"
#
# For each given object `object` that is an Integer, the value is considered a
# codepoint and converted to a character before concatenation:
#
# s = 'foo'
# s.concat(32, 'bar', 32, 'baz') # => "foo bar baz"
#
# Related: String#<<, which takes a single argument.
#
def concat: (*string | Integer str_or_codepoint) -> String
# <!--
# rdoc-file=string.c
# - str.count([other_str]+) -> integer
# -->
# Each `other_str` parameter defines a set of characters to count. The
# intersection of these sets defines the characters to count in `str`. Any
# `other_str` that starts with a caret `^` is negated. The sequence `c1-c2`
# means all characters between c1 and c2. The backslash character `\` can be
# used to escape `^` or `-` and is otherwise ignored unless it appears at the
# end of a sequence or the end of a `other_str`.
#
# a = "hello world"
# a.count "lo" #=> 5
# a.count "lo", "o" #=> 2
# a.count "hello", "^l" #=> 4
# a.count "ej-m" #=> 4
#
# "hello^world".count "\\^aeiou" #=> 4
# "hello-world".count "a\\-eo" #=> 4
#
# c = "hello world\\r\\n"
# c.count "\\" #=> 2
# c.count "\\A" #=> 0
# c.count "X-\\w" #=> 3
#
def count: (string other_str, *string other_strs) -> Integer
# <!--
# rdoc-file=string.c
# - str.crypt(salt_str) -> new_str
# -->
# Returns the string generated by calling `crypt(3)` standard library function
# with `str` and `salt_str`, in this order, as its arguments. Please do not use
# this method any longer. It is legacy; provided only for backward
# compatibility with ruby scripts in earlier days. It is bad to use in
# contemporary programs for several reasons:
#
# * Behaviour of C's `crypt(3)` depends on the OS it is run. The generated
# string lacks data portability.
#
# * On some OSes such as Mac OS, `crypt(3)` never fails (i.e. silently ends up
# in unexpected results).
#
# * On some OSes such as Mac OS, `crypt(3)` is not thread safe.
#
# * So-called "traditional" usage of `crypt(3)` is very very very weak.
# According to its manpage, Linux's traditional `crypt(3)` output has only
# 2**56 variations; too easy to brute force today. And this is the default
# behaviour.
#
# * In order to make things robust some OSes implement so-called "modular"
# usage. To go through, you have to do a complex build-up of the `salt_str`
# parameter, by hand. Failure in generation of a proper salt string tends
# not to yield any errors; typos in parameters are normally not detectable.
#
# * For instance, in the following example, the second invocation of
# String#crypt is wrong; it has a typo in "round=" (lacks "s"). However
# the call does not fail and something unexpected is generated.
#
# "foo".crypt("$5$rounds=1000$salt$") # OK, proper usage
# "foo".crypt("$5$round=1000$salt$") # Typo not detected
#
#
# * Even in the "modular" mode, some hash functions are considered archaic and
# no longer recommended at all; for instance module `$1$` is officially
# abandoned by its author: see http://phk.freebsd.dk/sagas/md5crypt_eol/ .
# For another instance module `$3$` is considered completely broken: see the
# manpage of FreeBSD.
#
# * On some OS such as Mac OS, there is no modular mode. Yet, as written
# above, `crypt(3)` on Mac OS never fails. This means even if you build up a
# proper salt string it generates a traditional DES hash anyways, and there
# is no way for you to be aware of.
#
# "foo".crypt("$5$rounds=1000$salt$") # => "$5fNPQMxC5j6."
#
#
# If for some reason you cannot migrate to other secure contemporary password
# hashing algorithms, install the string-crypt gem and `require 'string/crypt'`
# to continue using it.
#
def crypt: (string salt_str) -> String
# <!--
# rdoc-file=string.c
# - str.delete([other_str]+) -> new_str
# -->
# Returns a copy of *str* with all characters in the intersection of its
# arguments deleted. Uses the same rules for building the set of characters as
# String#count.
#
# "hello".delete "l","lo" #=> "heo"
# "hello".delete "lo" #=> "he"
# "hello".delete "aeiou", "^e" #=> "hell"
# "hello".delete "ej-m" #=> "ho"
#
def delete: (string other_str, *string other_strs) -> String
# <!--
# rdoc-file=string.c
# - str.delete!([other_str]+) -> str or nil
# -->
# Performs a `delete` operation in place, returning *str*, or `nil` if *str* was
# not modified.
#
def delete!: (string other_str, *string other_strs) -> String?
# <!--
# rdoc-file=string.c
# - str.delete_prefix(prefix) -> new_str
# -->
# Returns a copy of *str* with leading `prefix` deleted.
#
# "hello".delete_prefix("hel") #=> "lo"
# "hello".delete_prefix("llo") #=> "hello"
#
def delete_prefix: (string prefix) -> String
# <!--
# rdoc-file=string.c
# - str.delete_prefix!(prefix) -> self or nil
# -->
# Deletes leading `prefix` from *str*, returning `nil` if no change was made.
#
# "hello".delete_prefix!("hel") #=> "lo"
# "hello".delete_prefix!("llo") #=> nil
#
def delete_prefix!: (string prefix) -> String?
# <!--
# rdoc-file=string.c
# - str.delete_suffix(suffix) -> new_str
# -->
# Returns a copy of *str* with trailing `suffix` deleted.
#
# "hello".delete_suffix("llo") #=> "he"
# "hello".delete_suffix("hel") #=> "hello"
#
def delete_suffix: (string suffix) -> String
# <!--
# rdoc-file=string.c
# - str.delete_suffix!(suffix) -> self or nil
# -->
# Deletes trailing `suffix` from *str*, returning `nil` if no change was made.
#
# "hello".delete_suffix!("llo") #=> "he"
# "hello".delete_suffix!("hel") #=> nil
#
def delete_suffix!: (string suffix) -> String?
# <!--
# rdoc-file=string.c
# - downcase(*options) -> string
# -->
# Returns a string containing the downcased characters in `self`:
#
# s = 'Hello World!' # => "Hello World!"
# s.downcase # => "hello world!"
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#downcase!, String#upcase, String#upcase!.
#
def downcase: () -> String
| (:ascii | :fold | :lithuanian | :turkic) -> String
| (:lithuanian, :turkic) -> String
| (:turkic, :lithuanian) -> String
# <!--
# rdoc-file=string.c
# - downcase!(*options) -> self or nil
# -->
# Downcases the characters in `self`; returns `self` if any changes were made,
# `nil` otherwise:
#
# s = 'Hello World!' # => "Hello World!"
# s.downcase! # => "hello world!"
# s # => "hello world!"
# s.downcase! # => nil
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#downcase, String#upcase, String#upcase!.
#
def downcase!: () -> String?
| (:ascii | :fold | :lithuanian | :turkic) -> String?
| (:lithuanian, :turkic) -> String?
| (:turkic, :lithuanian) -> String?
# <!--
# rdoc-file=string.c
# - dump -> string
# -->
# Returns a printable version of `self`, enclosed in double-quotes, with special
# characters escaped, and with non-printing characters replaced by hexadecimal
# notation:
#
# "hello \n ''".dump # => "\"hello \\n ''\""
# "\f\x00\xff\\\"".dump # => "\"\\f\\x00\\xFF\\\\\\\"\""
#
# Related: String#undump (inverse of String#dump).
#
def dump: () -> String
# <!--
# rdoc-file=string.c
# - str.each_byte {|integer| block } -> str
# - str.each_byte -> an_enumerator
# -->
# Passes each byte in *str* to the given block, or returns an enumerator if no
# block is given.
#
# "hello".each_byte {|c| print c, ' ' }
#
# *produces:*
#
# 104 101 108 108 111
#
def each_byte: () { (Integer byte) -> void } -> self
| () -> ::Enumerator[Integer, self]
# <!--
# rdoc-file=string.c
# - str.each_char {|cstr| block } -> str
# - str.each_char -> an_enumerator
# -->
# Passes each character in *str* to the given block, or returns an enumerator if
# no block is given.
#
# "hello".each_char {|c| print c, ' ' }
#
# *produces:*
#
# h e l l o
#
def each_char: () { (String char) -> void } -> self
| () -> ::Enumerator[String, self]
# <!--
# rdoc-file=string.c
# - str.each_codepoint {|integer| block } -> str
# - str.each_codepoint -> an_enumerator
# -->
# Passes the Integer ordinal of each character in *str*, also known as a
# *codepoint* when applied to Unicode strings to the given block. For encodings
# other than UTF-8/UTF-16(BE|LE)/UTF-32(BE|LE), values are directly derived from
# the binary representation of each character.
#
# If no block is given, an enumerator is returned instead.
#
# "hello\u0639".each_codepoint {|c| print c, ' ' }
#
# *produces:*
#
# 104 101 108 108 111 1593
#
def each_codepoint: () { (Integer codepoint) -> void } -> self
| () -> ::Enumerator[Integer, self]
# <!--
# rdoc-file=string.c
# - str.each_grapheme_cluster {|cstr| block } -> str
# - str.each_grapheme_cluster -> an_enumerator
# -->
# Passes each grapheme cluster in *str* to the given block, or returns an
# enumerator if no block is given. Unlike String#each_char, this enumerates by
# grapheme clusters defined by Unicode Standard Annex #29
# http://unicode.org/reports/tr29/
#
# "a\u0300".each_char.to_a.size #=> 2
# "a\u0300".each_grapheme_cluster.to_a.size #=> 1
#
def each_grapheme_cluster: () { (String grapheme) -> void } -> self
| () -> ::Enumerator[String, self]
# <!--
# rdoc-file=string.c
# - str.each_line(separator=$/, chomp: false) {|substr| block } -> str
# - str.each_line(separator=$/, chomp: false) -> an_enumerator
# -->
# Splits *str* using the supplied parameter as the record separator (`$/` by
# default), passing each substring in turn to the supplied block. If a
# zero-length record separator is supplied, the string is split into paragraphs
# delimited by multiple successive newlines.
#
# If `chomp` is `true`, `separator` will be removed from the end of each line.
#
# If no block is given, an enumerator is returned instead.
#
# "hello\nworld".each_line {|s| p s}
# # prints:
# # "hello\n"
# # "world"
#
# "hello\nworld".each_line('l') {|s| p s}
# # prints:
# # "hel"
# # "l"
# # "o\nworl"
# # "d"
#
# "hello\n\n\nworld".each_line('') {|s| p s}
# # prints
# # "hello\n\n"
# # "world"
#
# "hello\nworld".each_line(chomp: true) {|s| p s}
# # prints:
# # "hello"
# # "world"
#
# "hello\nworld".each_line('l', chomp: true) {|s| p s}
# # prints:
# # "he"
# # ""
# # "o\nwor"
# # "d"
#
def each_line: (?string separator, ?chomp: boolish) { (String line) -> void } -> self
| (?string separator, ?chomp: boolish) -> Enumerator[String, self]
# <!--
# rdoc-file=string.c
# - empty? -> true or false
# -->
# Returns `true` if the length of `self` is zero, `false` otherwise:
#
# "hello".empty? # => false
# " ".empty? # => false
# "".empty? # => true
#
def empty?: () -> bool
# <!--
# rdoc-file=transcode.c
# - str.encode(encoding, **options) -> str
# - str.encode(dst_encoding, src_encoding, **options) -> str
# - str.encode(**options) -> str
# -->
# The first form returns a copy of `str` transcoded to encoding `encoding`. The
# second form returns a copy of `str` transcoded from src_encoding to
# dst_encoding. The last form returns a copy of `str` transcoded to
# `Encoding.default_internal`.
#
# By default, the first and second form raise Encoding::UndefinedConversionError
# for characters that are undefined in the destination encoding, and
# Encoding::InvalidByteSequenceError for invalid byte sequences in the source
# encoding. The last form by default does not raise exceptions but uses
# replacement strings.
#
# The `options` keyword arguments give details for conversion. The arguments
# are:
#
# :invalid
# : If the value is `:replace`, #encode replaces invalid byte sequences in
# `str` with the replacement character. The default is to raise the
# Encoding::InvalidByteSequenceError exception
# :undef
# : If the value is `:replace`, #encode replaces characters which are
# undefined in the destination encoding with the replacement character. The
# default is to raise the Encoding::UndefinedConversionError.
# :replace
# : Sets the replacement string to the given value. The default replacement
# string is "uFFFD" for Unicode encoding forms, and "?" otherwise.
# :fallback
# : Sets the replacement string by the given object for undefined character.
# The object should be a Hash, a Proc, a Method, or an object which has []
# method. Its key is an undefined character encoded in the source encoding
# of current transcoder. Its value can be any encoding until it can be
# converted into the destination encoding of the transcoder.
# :xml
# : The value must be `:text` or `:attr`. If the value is `:text` #encode
# replaces undefined characters with their (upper-case hexadecimal) numeric
# character references. '&', '<', and '>' are converted to "&", "<",
# and ">", respectively. If the value is `:attr`, #encode also quotes the
# replacement result (using '"'), and replaces '"' with """.
# :cr_newline
# : Replaces LF ("n") with CR ("r") if value is true.
# :crlf_newline
# : Replaces LF ("n") with CRLF ("r\n") if value is true.
# :universal_newline
# : Replaces CRLF ("r\n") and CR ("r") with LF ("n") if value is true.
#
def encode: (?encoding encoding, ?encoding from_encoding, ?invalid: :replace ?, ?undef: :replace ?, ?replace: String, ?fallback: String::encode_fallback, ?xml: :text | :attr, ?universal_newline: true, ?cr_newline: true, ?crlf_newline: true) -> String
# <!--
# rdoc-file=transcode.c
# - str.encode!(encoding, **options) -> str
# - str.encode!(dst_encoding, src_encoding, **options) -> str
# -->
# The first form transcodes the contents of *str* from str.encoding to
# `encoding`. The second form transcodes the contents of *str* from src_encoding
# to dst_encoding. The `options` keyword arguments give details for conversion.
# See String#encode for details. Returns the string even if no changes were
# made.
#
def encode!: (?encoding encoding, ?encoding from_encoding, ?invalid: :replace ?, ?undef: :replace ?, ?replace: String, ?fallback: String::encode_fallback, ?xml: :text | :attr, ?universal_newline: true, ?cr_newline: true, ?crlf_newline: true) -> self
# <!--
# rdoc-file=string.c
# - obj.encoding -> encoding
# -->
# Returns the Encoding object that represents the encoding of obj.
#
def encoding: () -> Encoding
# <!--
# rdoc-file=string.c
# - str.end_with?([suffixes]+) -> true or false
# -->
# Returns true if `str` ends with one of the `suffixes` given.
#
# "hello".end_with?("ello") #=> true
#
# # returns true if one of the +suffixes+ matches.
# "hello".end_with?("heaven", "ello") #=> true
# "hello".end_with?("heaven", "paradise") #=> false
#
def end_with?: (*string suffixes) -> bool
# <!--
# rdoc-file=string.c
# - eql?(object) -> true or false
# -->
# Returns `true` if `object` has the same length and content; as `self`; `false`
# otherwise:
#
# s = 'foo'
# s.eql?('foo') # => true
# s.eql?('food') # => false
# s.eql?('FOO') # => false
#
# Returns `false` if the two strings' encodings are not compatible:
#
# "\u{e4 f6 fc}".encode("ISO-8859-1").eql?("\u{c4 d6 dc}") # => false
#
def eql?: (untyped other) -> bool
# <!--
# rdoc-file=string.c
# - str.force_encoding(encoding) -> str
# -->
# Changes the encoding to `encoding` and returns self.
#
def force_encoding: (string | Encoding encoding) -> self
# <!--
# rdoc-file=string.c
# - freeze()
# -->
#
def freeze: () -> self
# <!--
# rdoc-file=string.c
# - getbyte(index) -> integer
# -->
# Returns the byte at zero-based `index` as an integer:
#
# s = 'abcde' # => "abcde"
# s.getbyte(0) # => 97
# s.getbyte(1) # => 98
#
# Related: String#setbyte.
#
def getbyte: (int index) -> Integer?
# <!--
# rdoc-file=string.c
# - str.grapheme_clusters -> an_array
# -->
# Returns an array of grapheme clusters in *str*. This is a shorthand for
# `str.each_grapheme_cluster.to_a`.
#
# If a block is given, which is a deprecated form, works the same as
# `each_grapheme_cluster`.
#
def grapheme_clusters: () -> ::Array[::String]
# <!--
# rdoc-file=string.c
# - gsub(pattern, replacement) -> new_string
# - gsub(pattern) {|match| ... } -> new_string
# - gsub(pattern) -> enumerator
# -->
# Returns a copy of `self` with all occurrences of the given `pattern` replaced.
#
# See [Substitution Methods](#class-String-label-Substitution+Methods).
#
# Returns an Enumerator if no `replacement` and no block given.
#
# Related: String#sub, String#sub!, String#gsub!.
#
def gsub: (Regexp | string pattern, string replacement) -> String
| (Regexp | string pattern, Hash[String, String] hash) -> String
| (Regexp | string pattern) { (String match) -> _ToS } -> String
| (Regexp | string pattern) -> ::Enumerator[String, self]
# <!--
# rdoc-file=string.c
# - gsub!(pattern, replacement) -> self or nil
# - gsub!(pattern) {|match| ... } -> self or nil
# - gsub!(pattern) -> an_enumerator
# -->
# Performs the specified substring replacement(s) on `self`; returns `self` if
# any replacement occurred, `nil` otherwise.
#
# See [Substitution Methods](#class-String-label-Substitution+Methods).
#
# Returns an Enumerator if no `replacement` and no block given.
#
# Related: String#sub, String#gsub, String#sub!.
#
def gsub!: (Regexp | string pattern, string replacement) -> String?
| (Regexp | string pattern, Hash[String, String] hash) -> String?
| (Regexp | string pattern) { (String match) -> _ToS } -> String?
| (Regexp | string pattern) -> ::Enumerator[String, self]
# <!--
# rdoc-file=string.c
# - hash -> integer
# -->
# Returns the integer hash value for `self`. The value is based on the length,
# content and encoding of `self`.
#
# Related: Object#hash.
#
def hash: () -> Integer
# <!--
# rdoc-file=string.c
# - str.hex -> integer
# -->
# Treats leading characters from *str* as a string of hexadecimal digits (with
# an optional sign and an optional `0x`) and returns the corresponding number.
# Zero is returned on error.
#
# "0x0a".hex #=> 10
# "-1234".hex #=> -4660
# "0".hex #=> 0
# "wombat".hex #=> 0
#
def hex: () -> Integer
# <!--
# rdoc-file=string.c
# - include? other_string -> true or false
# -->
# Returns `true` if `self` contains `other_string`, `false` otherwise:
#
# s = 'foo'
# s.include?('f') # => true
# s.include?('fo') # => true
# s.include?('food') # => false
#
def include?: (string other_str) -> bool
# <!--
# rdoc-file=string.c
# - index(substring, offset = 0) -> integer or nil
# - index(regexp, offset = 0) -> integer or nil
# -->
# Returns the Integer index of the first occurrence of the given `substring`, or
# `nil` if none found:
#
# 'foo'.index('f') # => 0
# 'foo'.index('o') # => 1
# 'foo'.index('oo') # => 1
# 'foo'.index('ooo') # => nil
#
# Returns the Integer index of the first match for the given Regexp `regexp`, or
# `nil` if none found:
#
# 'foo'.index(/f/) # => 0
# 'foo'.index(/o/) # => 1
# 'foo'.index(/oo/) # => 1
# 'foo'.index(/ooo/) # => nil
#
# Integer argument `offset`, if given, specifies the position in the string to
# begin the search:
#
# 'foo'.index('o', 1) # => 1
# 'foo'.index('o', 2) # => 2
# 'foo'.index('o', 3) # => nil
#
# If `offset` is negative, counts backward from the end of `self`:
#
# 'foo'.index('o', -1) # => 2
# 'foo'.index('o', -2) # => 1
# 'foo'.index('o', -3) # => 1
# 'foo'.index('o', -4) # => nil
#
# Related: String#rindex.
#
def index: (Regexp | string substr_or_regexp, ?int offset) -> Integer?
# <!--
# rdoc-file=string.c
# - insert(index, other_string) -> self
# -->
# Inserts the given `other_string` into `self`; returns `self`.
#
# If the Integer `index` is positive, inserts `other_string` at offset `index`:
#
# 'foo'.insert(1, 'bar') # => "fbaroo"
#
# If the Integer `index` is negative, counts backward from the end of `self` and
# inserts `other_string` at offset `index+1` (that is, *after* `self[index]`):
#
# 'foo'.insert(-2, 'bar') # => "fobaro"
#
def insert: (int index, string other_str) -> String
# <!--
# rdoc-file=string.c
# - inspect -> string
# -->
# Returns a printable version of `self`, enclosed in double-quotes, and with
# special characters escaped:
#
# s = "foo\tbar\tbaz\n"
# # => "foo\tbar\tbaz\n"
# s.inspect
# # => "\"foo\\tbar\\tbaz\\n\""
#
def inspect: () -> String
# <!--
# rdoc-file=string.c
# - str.intern -> symbol
# - str.to_sym -> symbol
# -->
# Returns the Symbol corresponding to *str*, creating the symbol if it did not
# previously exist. See Symbol#id2name.
#
# "Koala".intern #=> :Koala
# s = 'cat'.to_sym #=> :cat
# s == :cat #=> true
# s = '@cat'.to_sym #=> :@cat
# s == :@cat #=> true
#
# This can also be used to create symbols that cannot be represented using the
# `:xxx` notation.
#
# 'cat and dog'.to_sym #=> :"cat and dog"
#
def intern: () -> Symbol
# <!--
# rdoc-file=string.c
# - length -> integer
# -->
# Returns the count of characters (not bytes) in `self`:
#
# "\x80\u3042".length # => 2
# "hello".length # => 5
#
# String#size is an alias for String#length.
#
# Related: String#bytesize.
#
def length: () -> Integer
# <!--
# rdoc-file=string.c
# - str.lines(separator=$/, chomp: false) -> an_array
# -->
# Returns an array of lines in *str* split using the supplied record separator
# (`$/` by default). This is a shorthand for `str.each_line(separator,
# getline_args).to_a`.
#
# If `chomp` is `true`, `separator` will be removed from the end of each line.
#
# "hello\nworld\n".lines #=> ["hello\n", "world\n"]
# "hello world".lines(' ') #=> ["hello ", " ", "world"]
# "hello\nworld\n".lines(chomp: true) #=> ["hello", "world"]
#
# If a block is given, which is a deprecated form, works the same as
# `each_line`.
#
def lines: (?string separator, ?chomp: boolish) -> Array[String]
# <!--
# rdoc-file=string.c
# - str.ljust(integer, padstr=' ') -> new_str
# -->
# If *integer* is greater than the length of *str*, returns a new String of
# length *integer* with *str* left justified and padded with *padstr*;
# otherwise, returns *str*.
#
# "hello".ljust(4) #=> "hello"
# "hello".ljust(20) #=> "hello "
# "hello".ljust(20, '1234') #=> "hello123412341234123"
#
def ljust: (int integer, ?string padstr) -> String
# <!--
# rdoc-file=string.c
# - str.lstrip -> new_str
# -->
# Returns a copy of the receiver with leading whitespace removed. See also
# String#rstrip and String#strip.
#
# Refer to String#strip for the definition of whitespace.
#
# " hello ".lstrip #=> "hello "
# "hello".lstrip #=> "hello"
#
def lstrip: () -> String
# <!--
# rdoc-file=string.c
# - str.lstrip! -> self or nil
# -->
# Removes leading whitespace from the receiver. Returns the altered receiver, or
# `nil` if no change was made. See also String#rstrip! and String#strip!.
#
# Refer to String#strip for the definition of whitespace.
#
# " hello ".lstrip! #=> "hello "
# "hello ".lstrip! #=> nil
# "hello".lstrip! #=> nil
#
def lstrip!: () -> self?
# <!--
# rdoc-file=string.c
# - match(pattern, offset = 0) -> matchdata or nil
# - match(pattern, offset = 0) {|matchdata| ... } -> object
# -->
# Returns a Matchdata object (or `nil`) based on `self` and the given `pattern`.
#
# Note: also updates [Regexp-related global
# variables](Regexp.html#class-Regexp-label-Special+global+variables).
#
# * Computes `regexp` by converting `pattern` (if not already a Regexp).
# regexp = Regexp.new(pattern)
#
# * Computes `matchdata`, which will be either a MatchData object or `nil`
# (see Regexp#match):
# matchdata = <tt>regexp.match(self)
#
#
# With no block given, returns the computed `matchdata`:
#
# 'foo'.match('f') # => #<MatchData "f">
# 'foo'.match('o') # => #<MatchData "o">
# 'foo'.match('x') # => nil
#
# If Integer argument `offset` is given, the search begins at index `offset`:
#
# 'foo'.match('f', 1) # => nil
# 'foo'.match('o', 1) # => #<MatchData "o">
#
# With a block given, calls the block with the computed `matchdata` and returns
# the block's return value:
#
# 'foo'.match(/o/) {|matchdata| matchdata } # => #<MatchData "o">
# 'foo'.match(/x/) {|matchdata| matchdata } # => nil
# 'foo'.match(/f/, 1) {|matchdata| matchdata } # => nil
#
def match: (Regexp | string pattern, ?int pos) -> MatchData?
| [A] (Regexp | string pattern, ?int pos) { (MatchData) -> A } -> A
# <!--
# rdoc-file=string.c
# - match?(pattern, offset = 0) -> true or false
# -->
# Returns `true` or `false` based on whether a match is found for `self` and
# `pattern`.
#
# Note: does not update [Regexp-related global
# variables](Regexp.html#class-Regexp-label-Special+global+variables).
#
# Computes `regexp` by converting `pattern` (if not already a Regexp).
# regexp = Regexp.new(pattern)
#
# Returns `true` if `self+.match(regexp)` returns a Matchdata object, `false`
# otherwise:
#
# 'foo'.match?(/o/) # => true
# 'foo'.match?('o') # => true
# 'foo'.match?(/x/) # => false
#
# If Integer argument `offset` is given, the search begins at index `offset`:
# 'foo'.match?('f', 1) # => false
# 'foo'.match?('o', 1) # => true
#
def match?: (Regexp | string pattern, ?int pos) -> bool
# <!-- rdoc-file=string.c -->
# Returns the successor to `self`. The successor is calculated by incrementing
# characters.
#
# The first character to be incremented is the rightmost alphanumeric: or, if no
# alphanumerics, the rightmost character:
#
# 'THX1138'.succ # => "THX1139"
# '<<koala>>'.succ # => "<<koalb>>"
# '***'.succ # => '**+'
#
# The successor to a digit is another digit, "carrying" to the next-left
# character for a "rollover" from 9 to 0, and prepending another digit if
# necessary:
#
# '00'.succ # => "01"
# '09'.succ # => "10"
# '99'.succ # => "100"
#
# The successor to a letter is another letter of the same case, carrying to the
# next-left character for a rollover, and prepending another same-case letter if
# necessary:
#
# 'aa'.succ # => "ab"
# 'az'.succ # => "ba"
# 'zz'.succ # => "aaa"
# 'AA'.succ # => "AB"
# 'AZ'.succ # => "BA"
# 'ZZ'.succ # => "AAA"
#
# The successor to a non-alphanumeric character is the next character in the
# underlying character set's collating sequence, carrying to the next-left
# character for a rollover, and prepending another character if necessary:
#
# s = 0.chr * 3
# s # => "\x00\x00\x00"
# s.succ # => "\x00\x00\x01"
# s = 255.chr * 3
# s # => "\xFF\xFF\xFF"
# s.succ # => "\x01\x00\x00\x00"
#
# Carrying can occur between and among mixtures of alphanumeric characters:
#
# s = 'zz99zz99'
# s.succ # => "aaa00aa00"
# s = '99zz99zz'
# s.succ # => "100aa00aa"
#
# The successor to an empty String is a new empty String:
#
# ''.succ # => ""
#
# String#next is an alias for String#succ.
#
def next: () -> String
# <!-- rdoc-file=string.c -->
# Equivalent to String#succ, but modifies `self` in place; returns `self`.
#
# String#next! is an alias for String#succ!.
#
def next!: () -> self
# <!--
# rdoc-file=string.c
# - str.oct -> integer
# -->
# Treats leading characters of *str* as a string of octal digits (with an
# optional sign) and returns the corresponding number. Returns 0 if the
# conversion fails.
#
# "123".oct #=> 83
# "-377".oct #=> -255
# "bad".oct #=> 0
# "0377bad".oct #=> 255
#
# If `str` starts with `0`, radix indicators are honored. See Kernel#Integer.
#
def oct: () -> Integer
# <!--
# rdoc-file=string.c
# - str.ord -> integer
# -->
# Returns the Integer ordinal of a one-character string.
#
# "a".ord #=> 97
#
def ord: () -> Integer
# <!--
# rdoc-file=string.c
# - str.partition(sep) -> [head, sep, tail]
# - str.partition(regexp) -> [head, match, tail]
# -->
# Searches *sep* or pattern (*regexp*) in the string and returns the part before
# it, the match, and the part after it. If it is not found, returns two empty
# strings and *str*.
#
# "hello".partition("l") #=> ["he", "l", "lo"]
# "hello".partition("x") #=> ["hello", "", ""]
# "hello".partition(/.l/) #=> ["h", "el", "lo"]
#
def partition: (Regexp | string sep_or_regexp) -> [ String, String, String ]
# <!--
# rdoc-file=string.c
# - prepend(*other_strings) -> string
# -->
# Prepends each string in `other_strings` to `self` and returns `self`:
#
# s = 'foo'
# s.prepend('bar', 'baz') # => "barbazfoo"
# s # => "barbazfoo"
#
# Related: String#concat.
#
def prepend: (*string other_strs) -> String
# <!-- rdoc-file=string.c -->
# Replaces the contents of `self` with the contents of `other_string`:
#
# s = 'foo' # => "foo"
# s.replace('bar') # => "bar"
#
def replace: (string other_str) -> String
# <!--
# rdoc-file=string.c
# - reverse -> string
# -->
# Returns a new string with the characters from `self` in reverse order.
#
# 'stressed'.reverse # => "desserts"
#
def reverse: () -> String
# <!--
# rdoc-file=string.c
# - reverse! -> self
# -->
# Returns `self` with its characters reversed:
#
# s = 'stressed'
# s.reverse! # => "desserts"
# s # => "desserts"
#
def reverse!: () -> self
# <!--
# rdoc-file=string.c
# - rindex(substring, offset = self.length) -> integer or nil
# - rindex(regexp, offset = self.length) -> integer or nil
# -->
# Returns the Integer index of the *last* occurrence of the given `substring`,
# or `nil` if none found:
#
# 'foo'.rindex('f') # => 0
# 'foo'.rindex('o') # => 2
# 'foo'.rindex('oo') # => 1
# 'foo'.rindex('ooo') # => nil
#
# Returns the Integer index of the *last* match for the given Regexp `regexp`,
# or `nil` if none found:
#
# 'foo'.rindex(/f/) # => 0
# 'foo'.rindex(/o/) # => 2
# 'foo'.rindex(/oo/) # => 1
# 'foo'.rindex(/ooo/) # => nil
#
# The *last* match means starting at the possible last position, not the last of
# longest matches.
#
# 'foo'.rindex(/o+/) # => 2
# $~ #=> #<MatchData "o">
#
# To get the last longest match, needs to combine with negative lookbehind.
#
# 'foo'.rindex(/(?<!o)o+/) # => 1
# $~ #=> #<MatchData "oo">
#
# Or String#index with negative lookforward.
#
# 'foo'.index(/o+(?!.*o)/) # => 1
# $~ #=> #<MatchData "oo">
#
# Integer argument `offset`, if given and non-negative, specifies the maximum
# starting position in the
# string to _end_ the search:
#
# 'foo'.rindex('o', 0) # => nil
# 'foo'.rindex('o', 1) # => 1
# 'foo'.rindex('o', 2) # => 2
# 'foo'.rindex('o', 3) # => 2
#
# If `offset` is a negative Integer, the maximum starting position in the string
# to *end* the search is the sum of the string's length and `offset`:
#
# 'foo'.rindex('o', -1) # => 2
# 'foo'.rindex('o', -2) # => 1
# 'foo'.rindex('o', -3) # => nil
# 'foo'.rindex('o', -4) # => nil
#
# Related: String#index.
#
def rindex: (string | Regexp substr_or_regexp, ?int pos) -> Integer?
# <!--
# rdoc-file=string.c
# - str.rjust(integer, padstr=' ') -> new_str
# -->
# If *integer* is greater than the length of *str*, returns a new String of
# length *integer* with *str* right justified and padded with *padstr*;
# otherwise, returns *str*.
#
# "hello".rjust(4) #=> "hello"
# "hello".rjust(20) #=> " hello"
# "hello".rjust(20, '1234') #=> "123412341234123hello"
#
def rjust: (int integer, ?string padstr) -> String
# <!--
# rdoc-file=string.c
# - str.rpartition(sep) -> [head, sep, tail]
# - str.rpartition(regexp) -> [head, match, tail]
# -->
# Searches *sep* or pattern (*regexp*) in the string from the end of the string,
# and returns the part before it, the match, and the part after it. If it is not
# found, returns two empty strings and *str*.
#
# "hello".rpartition("l") #=> ["hel", "l", "o"]
# "hello".rpartition("x") #=> ["", "", "hello"]
# "hello".rpartition(/.l/) #=> ["he", "ll", "o"]
#
# The match from the end means starting at the possible last position, not the
# last of longest matches.
#
# "hello".rpartition(/l+/) #=> ["hel", "l", "o"]
#
# To partition at the last longest match, needs to combine with negative
# lookbehind.
#
# "hello".rpartition(/(?<!l)l+/) #=> ["he", "ll", "o"]
#
# Or String#partition with negative lookforward.
#
# "hello".partition(/l+(?!.*l)/) #=> ["he", "ll", "o"]
#
def rpartition: (string | Regexp sep_or_regexp) -> [ String, String, String ]
# <!--
# rdoc-file=string.c
# - str.rstrip -> new_str
# -->
# Returns a copy of the receiver with trailing whitespace removed. See also
# String#lstrip and String#strip.
#
# Refer to String#strip for the definition of whitespace.
#
# " hello ".rstrip #=> " hello"
# "hello".rstrip #=> "hello"
#
def rstrip: () -> String
# <!--
# rdoc-file=string.c
# - str.rstrip! -> self or nil
# -->
# Removes trailing whitespace from the receiver. Returns the altered receiver,
# or `nil` if no change was made. See also String#lstrip! and String#strip!.
#
# Refer to String#strip for the definition of whitespace.
#
# " hello ".rstrip! #=> " hello"
# " hello".rstrip! #=> nil
# "hello".rstrip! #=> nil
#
def rstrip!: () -> self?
# <!--
# rdoc-file=string.c
# - str.scan(pattern) -> array
# - str.scan(pattern) {|match, ...| block } -> str
# -->
# Both forms iterate through *str*, matching the pattern (which may be a Regexp
# or a String). For each match, a result is generated and either added to the
# result array or passed to the block. If the pattern contains no groups, each
# individual result consists of the matched string, `$&`. If the pattern
# contains groups, each individual result is itself an array containing one
# entry per group.
#
# a = "cruel world"
# a.scan(/\w+/) #=> ["cruel", "world"]
# a.scan(/.../) #=> ["cru", "el ", "wor"]
# a.scan(/(...)/) #=> [["cru"], ["el "], ["wor"]]
# a.scan(/(..)(..)/) #=> [["cr", "ue"], ["l ", "wo"]]
#
# And the block form:
#
# a.scan(/\w+/) {|w| print "<<#{w}>> " }
# print "\n"
# a.scan(/(.)(.)/) {|x,y| print y, x }
# print "\n"
#
# *produces:*
#
# <<cruel>> <<world>>
# rceu lowlr
#
def scan: (Regexp | string pattern) -> Array[String | Array[String]]
| (Regexp | string pattern) { (String | Array[String]) -> void } -> self
# <!--
# rdoc-file=string.c
# - str.scrub -> new_str
# - str.scrub(repl) -> new_str
# - str.scrub{|bytes|} -> new_str
# -->
# If the string is invalid byte sequence then replace invalid bytes with given
# replacement character, else returns self. If block is given, replace invalid
# bytes with returned value of the block.
#
# "abc\u3042\x81".scrub #=> "abc\u3042\uFFFD"
# "abc\u3042\x81".scrub("*") #=> "abc\u3042*"
# "abc\u3042\xE3\x80".scrub{|bytes| '<'+bytes.unpack1('H*')+'>' } #=> "abc\u3042<e380>"
#
def scrub: (?string repl) -> String
| () { (String bytes) -> string } -> String
# <!--
# rdoc-file=string.c
# - str.scrub! -> str
# - str.scrub!(repl) -> str
# - str.scrub!{|bytes|} -> str
# -->
# If the string is invalid byte sequence then replace invalid bytes with given
# replacement character, else returns self. If block is given, replace invalid
# bytes with returned value of the block.
#
# "abc\u3042\x81".scrub! #=> "abc\u3042\uFFFD"
# "abc\u3042\x81".scrub!("*") #=> "abc\u3042*"
# "abc\u3042\xE3\x80".scrub!{|bytes| '<'+bytes.unpack1('H*')+'>' } #=> "abc\u3042<e380>"
#
def scrub!: (?string repl) -> self
| () { (String bytes) -> string } -> self
# <!--
# rdoc-file=string.c
# - setbyte(index, integer) -> integer
# -->
# Sets the byte at zero-based `index` to `integer`; returns `integer`:
#
# s = 'abcde' # => "abcde"
# s.setbyte(0, 98) # => 98
# s # => "bbcde"
#
# Related: String#getbyte.
#
def setbyte: (int index, int integer) -> int
# <!-- rdoc-file=string.c -->
# Returns the count of characters (not bytes) in `self`:
#
# "\x80\u3042".length # => 2
# "hello".length # => 5
#
# String#size is an alias for String#length.
#
# Related: String#bytesize.
#
alias size length
# <!-- rdoc-file=string.c -->
# Returns the substring of `self` specified by the arguments.
#
# When the single Integer argument `index` is given, returns the 1-character
# substring found in `self` at offset `index`:
#
# 'bar'[2] # => "r"
#
# Counts backward from the end of `self` if `index` is negative:
#
# 'foo'[-3] # => "f"
#
# Returns `nil` if `index` is out of range:
#
# 'foo'[3] # => nil
# 'foo'[-4] # => nil
#
# When the two Integer arguments `start` and `length` are given, returns the
# substring of the given `length` found in `self` at offset `start`:
#
# 'foo'[0, 2] # => "fo"
# 'foo'[0, 0] # => ""
#
# Counts backward from the end of `self` if `start` is negative:
#
# 'foo'[-2, 2] # => "oo"
#
# Special case: returns a new empty String if `start` is equal to the length of
# `self`:
#
# 'foo'[3, 2] # => ""
#
# Returns `nil` if `start` is out of range:
#
# 'foo'[4, 2] # => nil
# 'foo'[-4, 2] # => nil
#
# Returns the trailing substring of `self` if `length` is large:
#
# 'foo'[1, 50] # => "oo"
#
# Returns `nil` if `length` is negative:
#
# 'foo'[0, -1] # => nil
#
# When the single Range argument `range` is given, derives `start` and `length`
# values from the given `range`, and returns values as above:
#
# * `'foo'[0..1]` is equivalent to `'foo'[0, 2]`.
# * `'foo'[0...1]` is equivalent to `'foo'[0, 1]`.
#
#
# When the Regexp argument `regexp` is given, and the `capture` argument is `0`,
# returns the first matching substring found in `self`, or `nil` if none found:
#
# 'foo'[/o/] # => "o"
# 'foo'[/x/] # => nil
# s = 'hello there'
# s[/[aeiou](.)\1/] # => "ell"
# s[/[aeiou](.)\1/, 0] # => "ell"
#
# If argument `capture` is given and not `0`, it should be either an Integer
# capture group index or a String or Symbol capture group name; the method call
# returns only the specified capture (see [Regexp
# Capturing](Regexp.html#class-Regexp-label-Capturing)):
#
# s = 'hello there'
# s[/[aeiou](.)\1/, 1] # => "l"
# s[/(?<vowel>[aeiou])(?<non_vowel>[^aeiou])/, "non_vowel"] # => "l"
# s[/(?<vowel>[aeiou])(?<non_vowel>[^aeiou])/, :vowel] # => "e"
#
# If an invalid capture group index is given, `nil` is returned. If an invalid
# capture group name is given, `IndexError` is raised.
#
# When the single String argument `substring` is given, returns the substring
# from `self` if found, otherwise `nil`:
#
# 'foo'['oo'] # => "oo"
# 'foo'['xx'] # => nil
#
# String#slice is an alias for String#[].
#
alias slice []
# <!--
# rdoc-file=string.c
# - slice!(index) -> new_string or nil
# - slice!(start, length) -> new_string or nil
# - slice!(range) -> new_string or nil
# - slice!(regexp, capture = 0) -> new_string or nil
# - slice!(substring) -> new_string or nil
# -->
# Removes the substring of `self` specified by the arguments; returns the
# removed substring.
#
# See String#[] for details about the arguments that specify the substring.
#
# A few examples:
#
# string = "This is a string"
# string.slice!(2) #=> "i"
# string.slice!(3..6) #=> " is "
# string.slice!(/s.*t/) #=> "sa st"
# string.slice!("r") #=> "r"
# string #=> "Thing"
#
def slice!: (int integer, ?int integer) -> String?
| (Range[Integer] | Range[Integer?] range) -> String?
| (Regexp regexp, ?int | String capture) -> String?
| (String other_str) -> String?
# <!--
# rdoc-file=string.c
# - str.split(pattern=nil, [limit]) -> an_array
# - str.split(pattern=nil, [limit]) {|sub| block } -> str
# -->
# Divides *str* into substrings based on a delimiter, returning an array of
# these substrings.
#
# If *pattern* is a String, then its contents are used as the delimiter when
# splitting *str*. If *pattern* is a single space, *str* is split on whitespace,
# with leading and trailing whitespace and runs of contiguous whitespace
# characters ignored.
#
# If *pattern* is a Regexp, *str* is divided where the pattern matches. Whenever
# the pattern matches a zero-length string, *str* is split into individual
# characters. If *pattern* contains groups, the respective matches will be
# returned in the array as well.
#
# If *pattern* is `nil`, the value of `$;` is used. If `$;` is `nil` (which is
# the default), *str* is split on whitespace as if ' ' were specified.
#
# If the *limit* parameter is omitted, trailing null fields are suppressed. If
# *limit* is a positive number, at most that number of split substrings will be
# returned (captured groups will be returned as well, but are not counted
# towards the limit). If *limit* is `1`, the entire string is returned as the
# only entry in an array. If negative, there is no limit to the number of fields
# returned, and trailing null fields are not suppressed.
#
# When the input `str` is empty an empty Array is returned as the string is
# considered to have no fields to split.
#
# " now's the time ".split #=> ["now's", "the", "time"]
# " now's the time ".split(' ') #=> ["now's", "the", "time"]
# " now's the time".split(/ /) #=> ["", "now's", "", "the", "time"]
# "1, 2.34,56, 7".split(%r{,\s*}) #=> ["1", "2.34", "56", "7"]
# "hello".split(//) #=> ["h", "e", "l", "l", "o"]
# "hello".split(//, 3) #=> ["h", "e", "llo"]
# "hi mom".split(%r{\s*}) #=> ["h", "i", "m", "o", "m"]
#
# "mellow yellow".split("ello") #=> ["m", "w y", "w"]
# "1,2,,3,4,,".split(',') #=> ["1", "2", "", "3", "4"]
# "1,2,,3,4,,".split(',', 4) #=> ["1", "2", "", "3,4,,"]
# "1,2,,3,4,,".split(',', -4) #=> ["1", "2", "", "3", "4", "", ""]
#
# "1:2:3".split(/(:)()()/, 2) #=> ["1", ":", "", "", "2:3"]
#
# "".split(',', -1) #=> []
#
# If a block is given, invoke the block with each split substring.
#
def split: (?Regexp | string pattern, ?int limit) -> Array[String]
| (?Regexp | string pattern, ?int limit) { (String) -> void } -> self
# <!--
# rdoc-file=string.c
# - str.squeeze([other_str]*) -> new_str
# -->
# Builds a set of characters from the *other_str* parameter(s) using the
# procedure described for String#count. Returns a new string where runs of the
# same character that occur in this set are replaced by a single character. If
# no arguments are given, all runs of identical characters are replaced by a
# single character.
#
# "yellow moon".squeeze #=> "yelow mon"
# " now is the".squeeze(" ") #=> " now is the"
# "putters shoot balls".squeeze("m-z") #=> "puters shot balls"
#
def squeeze: (*string other_str) -> String
# <!--
# rdoc-file=string.c
# - str.squeeze!([other_str]*) -> str or nil
# -->
# Squeezes *str* in place, returning either *str*, or `nil` if no changes were
# made.
#
def squeeze!: (*string other_str) -> self?
# <!--
# rdoc-file=string.c
# - str.start_with?([prefixes]+) -> true or false
# -->
# Returns true if `str` starts with one of the `prefixes` given. Each of the
# `prefixes` should be a String or a Regexp.
#
# "hello".start_with?("hell") #=> true
# "hello".start_with?(/H/i) #=> true
#
# # returns true if one of the prefixes matches.
# "hello".start_with?("heaven", "hell") #=> true
# "hello".start_with?("heaven", "paradise") #=> false
#
def start_with?: (*string prefixes) -> bool
# <!--
# rdoc-file=string.c
# - str.strip -> new_str
# -->
# Returns a copy of the receiver with leading and trailing whitespace removed.
#
# Whitespace is defined as any of the following characters: null, horizontal
# tab, line feed, vertical tab, form feed, carriage return, space.
#
# " hello ".strip #=> "hello"
# "\tgoodbye\r\n".strip #=> "goodbye"
# "\x00\t\n\v\f\r ".strip #=> ""
# "hello".strip #=> "hello"
#
def strip: () -> String
# <!--
# rdoc-file=string.c
# - str.strip! -> self or nil
# -->
# Removes leading and trailing whitespace from the receiver. Returns the altered
# receiver, or `nil` if there was no change.
#
# Refer to String#strip for the definition of whitespace.
#
# " hello ".strip! #=> "hello"
# "hello".strip! #=> nil
#
def strip!: () -> self?
# <!--
# rdoc-file=string.c
# - sub(pattern, replacement) -> new_string
# - sub(pattern) {|match| ... } -> new_string
# -->
# Returns a copy of `self` with only the first occurrence (not all occurrences)
# of the given `pattern` replaced.
#
# See [Substitution Methods](#class-String-label-Substitution+Methods).
#
# Related: String#sub!, String#gsub, String#gsub!.
#
def sub: (Regexp | string pattern, string | Hash[String, String] replacement) -> String
| (Regexp | string pattern) { (String match) -> _ToS } -> String
# <!--
# rdoc-file=string.c
# - sub!(pattern, replacement) -> self or nil
# - sub!(pattern) {|match| ... } -> self or nil
# -->
# Returns `self` with only the first occurrence (not all occurrences) of the
# given `pattern` replaced.
#
# See [Substitution Methods](#class-String-label-Substitution+Methods).
#
# Related: String#sub, String#gsub, String#gsub!.
#
def sub!: (Regexp | string pattern, string | Hash[String, String] replacement) -> self?
| (Regexp | string pattern) { (String match) -> _ToS } -> String?
# <!--
# rdoc-file=string.c
# - succ -> new_str
# -->
# Returns the successor to `self`. The successor is calculated by incrementing
# characters.
#
# The first character to be incremented is the rightmost alphanumeric: or, if no
# alphanumerics, the rightmost character:
#
# 'THX1138'.succ # => "THX1139"
# '<<koala>>'.succ # => "<<koalb>>"
# '***'.succ # => '**+'
#
# The successor to a digit is another digit, "carrying" to the next-left
# character for a "rollover" from 9 to 0, and prepending another digit if
# necessary:
#
# '00'.succ # => "01"
# '09'.succ # => "10"
# '99'.succ # => "100"
#
# The successor to a letter is another letter of the same case, carrying to the
# next-left character for a rollover, and prepending another same-case letter if
# necessary:
#
# 'aa'.succ # => "ab"
# 'az'.succ # => "ba"
# 'zz'.succ # => "aaa"
# 'AA'.succ # => "AB"
# 'AZ'.succ # => "BA"
# 'ZZ'.succ # => "AAA"
#
# The successor to a non-alphanumeric character is the next character in the
# underlying character set's collating sequence, carrying to the next-left
# character for a rollover, and prepending another character if necessary:
#
# s = 0.chr * 3
# s # => "\x00\x00\x00"
# s.succ # => "\x00\x00\x01"
# s = 255.chr * 3
# s # => "\xFF\xFF\xFF"
# s.succ # => "\x01\x00\x00\x00"
#
# Carrying can occur between and among mixtures of alphanumeric characters:
#
# s = 'zz99zz99'
# s.succ # => "aaa00aa00"
# s = '99zz99zz'
# s.succ # => "100aa00aa"
#
# The successor to an empty String is a new empty String:
#
# ''.succ # => ""
#
# String#next is an alias for String#succ.
#
def succ: () -> String
# <!--
# rdoc-file=string.c
# - succ! -> self
# -->
# Equivalent to String#succ, but modifies `self` in place; returns `self`.
#
# String#next! is an alias for String#succ!.
#
def succ!: () -> String
# <!--
# rdoc-file=string.c
# - str.sum(n=16) -> integer
# -->
# Returns a basic *n*-bit checksum of the characters in *str*, where *n* is the
# optional Integer parameter, defaulting to 16. The result is simply the sum of
# the binary value of each byte in *str* modulo `2**n - 1`. This is not a
# particularly good checksum.
#
def sum: (?int n) -> Integer
# <!--
# rdoc-file=string.c
# - swapcase(*options) -> string
# -->
# Returns a string containing the characters in `self`, with cases reversed;
# each uppercase character is downcased; each lowercase character is upcased:
#
# s = 'Hello World!' # => "Hello World!"
# s.swapcase # => "hELLO wORLD!"
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#swapcase!.
#
def swapcase: () -> String
| (:ascii | :lithuanian | :turkic) -> String
| (:lithuanian, :turkic) -> String
| (:turkic, :lithuanian) -> String
# <!--
# rdoc-file=string.c
# - swapcase!(*options) -> self or nil
# -->
# Upcases each lowercase character in `self`; downcases uppercase character;
# returns `self` if any changes were made, `nil` otherwise:
#
# s = 'Hello World!' # => "Hello World!"
# s.swapcase! # => "hELLO wORLD!"
# s # => "Hello World!"
# ''.swapcase! # => nil
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#swapcase.
#
def swapcase!: () -> self?
| (:ascii | :lithuanian | :turkic) -> self?
| (:lithuanian, :turkic) -> self?
| (:turkic, :lithuanian) -> self?
# <!--
# rdoc-file=complex.c
# - str.to_c -> complex
# -->
# Returns a complex which denotes the string form. The parser ignores leading
# whitespaces and trailing garbage. Any digit sequences can be separated by an
# underscore. Returns zero for null or garbage string.
#
# '9'.to_c #=> (9+0i)
# '2.5'.to_c #=> (2.5+0i)
# '2.5/1'.to_c #=> ((5/2)+0i)
# '-3/2'.to_c #=> ((-3/2)+0i)
# '-i'.to_c #=> (0-1i)
# '45i'.to_c #=> (0+45i)
# '3-4i'.to_c #=> (3-4i)
# '-4e2-4e-2i'.to_c #=> (-400.0-0.04i)
# '-0.0-0.0i'.to_c #=> (-0.0-0.0i)
# '1/2+3/4i'.to_c #=> ((1/2)+(3/4)*i)
# 'ruby'.to_c #=> (0+0i)
#
# See Kernel.Complex.
#
def to_c: () -> Complex
# <!--
# rdoc-file=string.c
# - to_f -> float
# -->
# Returns the result of interpreting leading characters in `self` as a Float:
#
# '3.14159'.to_f # => 3.14159
# '1.234e-2'.to_f # => 0.01234
#
# Characters past a leading valid number (in the given `base`) are ignored:
#
# '3.14 (pi to two places)'.to_f # => 3.14
#
# Returns zero if there is no leading valid number:
#
# 'abcdef'.to_f # => 0.0
#
def to_f: () -> Float
# <!--
# rdoc-file=string.c
# - to_i(base = 10) -> integer
# -->
# Returns the result of interpreting leading characters in `self` as an integer
# in the given `base` (which must be in (2..36)):
#
# '123456'.to_i # => 123456
# '123def'.to_i(16) # => 1195503
#
# Characters past a leading valid number (in the given `base`) are ignored:
#
# '12.345'.to_i # => 12
# '12345'.to_i(2) # => 1
#
# Returns zero if there is no leading valid number:
#
# 'abcdef'.to_i # => 0
# '2'.to_i(2) # => 0
#
def to_i: (?int base) -> Integer
# <!--
# rdoc-file=rational.c
# - str.to_r -> rational
# -->
# Returns the result of interpreting leading characters in `str` as a rational.
# Leading whitespace and extraneous characters past the end of a valid number
# are ignored. Digit sequences can be separated by an underscore. If there is
# not a valid number at the start of `str`, zero is returned. This method never
# raises an exception.
#
# ' 2 '.to_r #=> (2/1)
# '300/2'.to_r #=> (150/1)
# '-9.2'.to_r #=> (-46/5)
# '-9.2e2'.to_r #=> (-920/1)
# '1_234_567'.to_r #=> (1234567/1)
# '21 June 09'.to_r #=> (21/1)
# '21/06/09'.to_r #=> (7/2)
# 'BWV 1079'.to_r #=> (0/1)
#
# NOTE: "0.3".to_r isn't the same as 0.3.to_r. The former is equivalent to
# "3/10".to_r, but the latter isn't so.
#
# "0.3".to_r == 3/10r #=> true
# 0.3.to_r == 3/10r #=> false
#
# See also Kernel#Rational.
#
def to_r: () -> Rational
# <!--
# rdoc-file=string.c
# - to_s -> self or string
# -->
# Returns `self` if `self` is a String, or `self` converted to a String if
# `self` is a subclass of String.
#
# String#to_str is an alias for String#to_s.
#
def to_s: () -> String
# <!-- rdoc-file=string.c -->
# Returns `self` if `self` is a String, or `self` converted to a String if
# `self` is a subclass of String.
#
# String#to_str is an alias for String#to_s.
#
def to_str: () -> String
# <!-- rdoc-file=string.c -->
# Returns the Symbol corresponding to *str*, creating the symbol if it did not
# previously exist. See Symbol#id2name.
#
# "Koala".intern #=> :Koala
# s = 'cat'.to_sym #=> :cat
# s == :cat #=> true
# s = '@cat'.to_sym #=> :@cat
# s == :@cat #=> true
#
# This can also be used to create symbols that cannot be represented using the
# `:xxx` notation.
#
# 'cat and dog'.to_sym #=> :"cat and dog"
#
def to_sym: () -> Symbol
# <!--
# rdoc-file=string.c
# - str.tr(from_str, to_str) => new_str
# -->
# Returns a copy of `str` with the characters in `from_str` replaced by the
# corresponding characters in `to_str`. If `to_str` is shorter than `from_str`,
# it is padded with its last character in order to maintain the correspondence.
#
# "hello".tr('el', 'ip') #=> "hippo"
# "hello".tr('aeiou', '*') #=> "h*ll*"
# "hello".tr('aeiou', 'AA*') #=> "hAll*"
#
# Both strings may use the `c1-c2` notation to denote ranges of characters, and
# `from_str` may start with a `^`, which denotes all characters except those
# listed.
#
# "hello".tr('a-y', 'b-z') #=> "ifmmp"
# "hello".tr('^aeiou', '*') #=> "*e**o"
#
# The backslash character `\` can be used to escape `^` or `-` and is otherwise
# ignored unless it appears at the end of a range or the end of the `from_str`
# or `to_str`:
#
# "hello^world".tr("\\^aeiou", "*") #=> "h*ll**w*rld"
# "hello-world".tr("a\\-eo", "*") #=> "h*ll**w*rld"
#
# "hello\r\nworld".tr("\r", "") #=> "hello\nworld"
# "hello\r\nworld".tr("\\r", "") #=> "hello\r\nwold"
# "hello\r\nworld".tr("\\\r", "") #=> "hello\nworld"
#
# "X['\\b']".tr("X\\", "") #=> "['b']"
# "X['\\b']".tr("X-\\]", "") #=> "'b'"
#
def tr: (string from_str, string to_str) -> String
# <!--
# rdoc-file=string.c
# - str.tr!(from_str, to_str) -> str or nil
# -->
# Translates *str* in place, using the same rules as String#tr. Returns *str*,
# or `nil` if no changes were made.
#
def tr!: (string from_str, string to_str) -> String?
# <!--
# rdoc-file=string.c
# - str.tr_s(from_str, to_str) -> new_str
# -->
# Processes a copy of *str* as described under String#tr, then removes duplicate
# characters in regions that were affected by the translation.
#
# "hello".tr_s('l', 'r') #=> "hero"
# "hello".tr_s('el', '*') #=> "h*o"
# "hello".tr_s('el', 'hx') #=> "hhxo"
#
def tr_s: (string from_str, string to_str) -> String
# <!--
# rdoc-file=string.c
# - str.tr_s!(from_str, to_str) -> str or nil
# -->
# Performs String#tr_s processing on *str* in place, returning *str*, or `nil`
# if no changes were made.
#
def tr_s!: (string from_str, string to_str) -> String?
# <!--
# rdoc-file=string.c
# - undump -> string
# -->
# Returns an unescaped version of `self`:
#
# s_orig = "\f\x00\xff\\\"" # => "\f\u0000\xFF\\\""
# s_dumped = s_orig.dump # => "\"\\f\\x00\\xFF\\\\\\\"\""
# s_undumped = s_dumped.undump # => "\f\u0000\xFF\\\""
# s_undumped == s_orig # => true
#
# Related: String#dump (inverse of String#undump).
#
def undump: () -> String
# <!--
# rdoc-file=string.c
# - str.unicode_normalize(form=:nfc)
# -->
# Unicode Normalization---Returns a normalized form of `str`, using Unicode
# normalizations NFC, NFD, NFKC, or NFKD. The normalization form used is
# determined by `form`, which can be any of the four values `:nfc`, `:nfd`,
# `:nfkc`, or `:nfkd`. The default is `:nfc`.
#
# If the string is not in a Unicode Encoding, then an Exception is raised. In
# this context, 'Unicode Encoding' means any of UTF-8, UTF-16BE/LE, and
# UTF-32BE/LE, as well as GB18030, UCS_2BE, and UCS_4BE. Anything other than
# UTF-8 is implemented by converting to UTF-8, which makes it slower than UTF-8.
#
# "a\u0300".unicode_normalize #=> "\u00E0"
# "a\u0300".unicode_normalize(:nfc) #=> "\u00E0"
# "\u00E0".unicode_normalize(:nfd) #=> "a\u0300"
# "\xE0".force_encoding('ISO-8859-1').unicode_normalize(:nfd)
# #=> Encoding::CompatibilityError raised
#
def unicode_normalize: (?:nfc | :nfd | :nfkc | :nfkd) -> String
# <!--
# rdoc-file=string.c
# - str.unicode_normalize!(form=:nfc)
# -->
# Destructive version of String#unicode_normalize, doing Unicode normalization
# in place.
#
def unicode_normalize!: (?:nfc | :nfd | :nfkc | :nfkd) -> String
# <!--
# rdoc-file=string.c
# - str.unicode_normalized?(form=:nfc)
# -->
# Checks whether `str` is in Unicode normalization form `form`, which can be any
# of the four values `:nfc`, `:nfd`, `:nfkc`, or `:nfkd`. The default is `:nfc`.
#
# If the string is not in a Unicode Encoding, then an Exception is raised. For
# details, see String#unicode_normalize.
#
# "a\u0300".unicode_normalized? #=> false
# "a\u0300".unicode_normalized?(:nfd) #=> true
# "\u00E0".unicode_normalized? #=> true
# "\u00E0".unicode_normalized?(:nfd) #=> false
# "\xE0".force_encoding('ISO-8859-1').unicode_normalized?
# #=> Encoding::CompatibilityError raised
#
def unicode_normalized?: (?:nfc | :nfd | :nfkc | :nfkd) -> bool
# <!--
# rdoc-file=pack.rb
# - str.unpack(format) -> anArray
# - str.unpack(format, offset: anInteger) -> anArray
# -->
# Decodes *str* (which may contain binary data) according to the format string,
# returning an array of each value extracted. The format string consists of a
# sequence of single-character directives, summarized in the table at the end of
# this entry. Each directive may be followed by a number, indicating the number
# of times to repeat with this directive. An asterisk (```*`'') will use up all
# remaining elements. The directives `sSiIlL` may each be followed by an
# underscore (```_`'') or exclamation mark (```!`'') to use the underlying
# platform's native size for the specified type; otherwise, it uses a
# platform-independent consistent size. Spaces are ignored in the format string.
#
# See also String#unpack1, Array#pack.
#
# "abc \0\0abc \0\0".unpack('A6Z6') #=> ["abc", "abc "]
# "abc \0\0".unpack('a3a3') #=> ["abc", " \000\000"]
# "abc \0abc \0".unpack('Z*Z*') #=> ["abc ", "abc "]
# "aa".unpack('b8B8') #=> ["10000110", "01100001"]
# "aaa".unpack('h2H2c') #=> ["16", "61", 97]
# "\xfe\xff\xfe\xff".unpack('sS') #=> [-2, 65534]
# "now=20is".unpack('M*') #=> ["now is"]
# "whole".unpack('xax2aX2aX1aX2a') #=> ["h", "e", "l", "l", "o"]
#
# This table summarizes the various formats and the Ruby classes returned by
# each.
#
# Integer | |
# Directive | Returns | Meaning
# ------------------------------------------------------------------
# C | Integer | 8-bit unsigned (unsigned char)
# S | Integer | 16-bit unsigned, native endian (uint16_t)
# L | Integer | 32-bit unsigned, native endian (uint32_t)
# Q | Integer | 64-bit unsigned, native endian (uint64_t)
# J | Integer | pointer width unsigned, native endian (uintptr_t)
# | |
# c | Integer | 8-bit signed (signed char)
# s | Integer | 16-bit signed, native endian (int16_t)
# l | Integer | 32-bit signed, native endian (int32_t)
# q | Integer | 64-bit signed, native endian (int64_t)
# j | Integer | pointer width signed, native endian (intptr_t)
# | |
# S_ S! | Integer | unsigned short, native endian
# I I_ I! | Integer | unsigned int, native endian
# L_ L! | Integer | unsigned long, native endian
# Q_ Q! | Integer | unsigned long long, native endian (ArgumentError
# | | if the platform has no long long type.)
# J! | Integer | uintptr_t, native endian (same with J)
# | |
# s_ s! | Integer | signed short, native endian
# i i_ i! | Integer | signed int, native endian
# l_ l! | Integer | signed long, native endian
# q_ q! | Integer | signed long long, native endian (ArgumentError
# | | if the platform has no long long type.)
# j! | Integer | intptr_t, native endian (same with j)
# | |
# S> s> S!> s!> | Integer | same as the directives without ">" except
# L> l> L!> l!> | | big endian
# I!> i!> | |
# Q> q> Q!> q!> | | "S>" is the same as "n"
# J> j> J!> j!> | | "L>" is the same as "N"
# | |
# S< s< S!< s!< | Integer | same as the directives without "<" except
# L< l< L!< l!< | | little endian
# I!< i!< | |
# Q< q< Q!< q!< | | "S<" is the same as "v"
# J< j< J!< j!< | | "L<" is the same as "V"
# | |
# n | Integer | 16-bit unsigned, network (big-endian) byte order
# N | Integer | 32-bit unsigned, network (big-endian) byte order
# v | Integer | 16-bit unsigned, VAX (little-endian) byte order
# V | Integer | 32-bit unsigned, VAX (little-endian) byte order
# | |
# U | Integer | UTF-8 character
# w | Integer | BER-compressed integer (see Array#pack)
#
# Float | |
# Directive | Returns | Meaning
# -----------------------------------------------------------------
# D d | Float | double-precision, native format
# F f | Float | single-precision, native format
# E | Float | double-precision, little-endian byte order
# e | Float | single-precision, little-endian byte order
# G | Float | double-precision, network (big-endian) byte order
# g | Float | single-precision, network (big-endian) byte order
#
# String | |
# Directive | Returns | Meaning
# -----------------------------------------------------------------
# A | String | arbitrary binary string (remove trailing nulls and ASCII spaces)
# a | String | arbitrary binary string
# Z | String | null-terminated string
# B | String | bit string (MSB first)
# b | String | bit string (LSB first)
# H | String | hex string (high nibble first)
# h | String | hex string (low nibble first)
# u | String | UU-encoded string
# M | String | quoted-printable, MIME encoding (see RFC2045)
# m | String | base64 encoded string (RFC 2045) (default)
# | | base64 encoded string (RFC 4648) if followed by 0
# P | String | pointer to a structure (fixed-length string)
# p | String | pointer to a null-terminated string
#
# Misc. | |
# Directive | Returns | Meaning
# -----------------------------------------------------------------
# @ | --- | skip to the offset given by the length argument
# X | --- | skip backward one byte
# x | --- | skip forward one byte
#
# The keyword *offset* can be given to start the decoding after skipping the
# specified amount of bytes:
# "abc".unpack("C*") # => [97, 98, 99]
# "abc".unpack("C*", offset: 2) # => [99]
# "abc".unpack("C*", offset: 4) # => offset outside of string (ArgumentError)
#
# HISTORY
#
# * J, J! j, and j! are available since Ruby 2.3.
# * Q_, Q!, q_, and q! are available since Ruby 2.1.
# * I!<, i!<, I!>, and i!> are available since Ruby 1.9.3.
#
def unpack: (String format, ?offset: Integer) -> Array[Integer | Float | String | nil]
# <!--
# rdoc-file=pack.rb
# - str.unpack1(format) -> obj
# - str.unpack1(format, offset: anInteger) -> obj
# -->
# Decodes *str* (which may contain binary data) according to the format string,
# returning the first value extracted.
#
# See also String#unpack, Array#pack.
#
# Contrast with String#unpack:
#
# "abc \0\0abc \0\0".unpack('A6Z6') #=> ["abc", "abc "]
# "abc \0\0abc \0\0".unpack1('A6Z6') #=> "abc"
#
# In that case data would be lost but often it's the case that the array only
# holds one value, especially when unpacking binary data. For instance:
#
# "\xff\x00\x00\x00".unpack("l") #=> [255]
# "\xff\x00\x00\x00".unpack1("l") #=> 255
#
# Thus unpack1 is convenient, makes clear the intention and signals the expected
# return value to those reading the code.
#
# The keyword *offset* can be given to start the decoding after skipping the
# specified amount of bytes:
# "abc".unpack1("C*") # => 97
# "abc".unpack1("C*", offset: 2) # => 99
# "abc".unpack1("C*", offset: 4) # => offset outside of string (ArgumentError)
#
def unpack1: (String format) -> (Integer | Float | String | nil)
# <!--
# rdoc-file=string.c
# - upcase(*options) -> string
# -->
# Returns a string containing the upcased characters in `self`:
#
# s = 'Hello World!' # => "Hello World!"
# s.upcase # => "HELLO WORLD!"
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#upcase!, String#downcase, String#downcase!.
#
def upcase: () -> String
| (:ascii | :lithuanian | :turkic) -> String
| (:lithuanian, :turkic) -> String
| (:turkic, :lithuanian) -> String
# <!--
# rdoc-file=string.c
# - upcase!(*options) -> self or nil
# -->
# Upcases the characters in `self`; returns `self` if any changes were made,
# `nil` otherwise:
#
# s = 'Hello World!' # => "Hello World!"
# s.upcase! # => "HELLO WORLD!"
# s # => "HELLO WORLD!"
# s.upcase! # => nil
#
# The casing may be affected by the given `options`; see [Case
# Mapping](doc/case_mapping_rdoc.html).
#
# Related: String#upcase, String#downcase, String#downcase!.
#
def upcase!: () -> self?
| (:ascii | :lithuanian | :turkic) -> self?
| (:lithuanian, :turkic) -> self?
| (:turkic, :lithuanian) -> self?
# <!--
# rdoc-file=string.c
# - upto(other_string, exclusive = false) {|string| ... } -> self
# - upto(other_string, exclusive = false) -> new_enumerator
# -->
# With a block given, calls the block with each String value returned by
# successive calls to String#succ; the first value is `self`, the next is
# `self.succ`, and so on; the sequence terminates when value `other_string` is
# reached; returns `self`:
#
# 'a8'.upto('b6') {|s| print s, ' ' } # => "a8"
#
# Output:
#
# a8 a9 b0 b1 b2 b3 b4 b5 b6
#
# If argument `exclusive` is given as a truthy object, the last value is
# omitted:
#
# 'a8'.upto('b6', true) {|s| print s, ' ' } # => "a8"
#
# Output:
#
# a8 a9 b0 b1 b2 b3 b4 b5
#
# If `other_string` would not be reached, does not call the block:
#
# '25'.upto('5') {|s| fail s }
# 'aa'.upto('a') {|s| fail s }
#
# With no block given, returns a new Enumerator:
#
# 'a8'.upto('b6') # => #<Enumerator: "a8":upto("b6")>
#
def upto: (string other_str, ?boolish exclusive) -> Enumerator[String, self]
| (string other_str, ?boolish exclusive) { (String s) -> void } -> self
# <!--
# rdoc-file=string.c
# - str.valid_encoding? -> true or false
# -->
# Returns true for a string which is encoded correctly.
#
# "\xc2\xa1".force_encoding("UTF-8").valid_encoding? #=> true
# "\xc2".force_encoding("UTF-8").valid_encoding? #=> false
# "\x80".force_encoding("UTF-8").valid_encoding? #=> false
#
def valid_encoding?: () -> bool
private
# <!--
# rdoc-file=string.c
# - String.new(string = '') -> new_string
# - String.new(string = '', encoding: encoding) -> new_string
# - String.new(string = '', capacity: size) -> new_string
# -->
# Returns a new String that is a copy of `string`.
#
# With no arguments, returns the empty string with the Encoding `ASCII-8BIT`:
# s = String.new
# s # => ""
# s.encoding # => #<Encoding:ASCII-8BIT>
#
# With the single String argument `string`, returns a copy of `string` with the
# same encoding as `string`:
# s = String.new("Que veut dire \u{e7}a?")
# s # => "Que veut dire \u{e7}a?"
# s.encoding # => #<Encoding:UTF-8>
#
# Literal strings like `""` or here-documents always use [script
# encoding](Encoding.html#class-Encoding-label-Script+encoding), unlike
# String.new.
#
# With keyword `encoding`, returns a copy of `str` with the specified encoding:
# s = String.new(encoding: 'ASCII')
# s.encoding # => #<Encoding:US-ASCII>
# s = String.new('foo', encoding: 'ASCII')
# s.encoding # => #<Encoding:US-ASCII>
#
# Note that these are equivalent:
# s0 = String.new('foo', encoding: 'ASCII')
# s1 = 'foo'.force_encoding('ASCII')
# s0.encoding == s1.encoding # => true
#
# With keyword `capacity`, returns a copy of `str`; the given `capacity` may set
# the size of the internal buffer, which may affect performance:
# String.new(capacity: 1) # => ""
# String.new(capacity: 4096) # => ""
#
# The `string`, `encoding`, and `capacity` arguments may all be used together:
#
# String.new('hello', encoding: 'UTF-8', capacity: 25)
#
def initialize: (?string str, ?encoding: encoding, ?capacity: int) -> void
# <!--
# rdoc-file=string.c
# - replace(other_string) -> self
# -->
# Replaces the contents of `self` with the contents of `other_string`:
#
# s = 'foo' # => "foo"
# s.replace('bar') # => "bar"
#
alias initialize_copy replace
end
interface _ArefFromStringToString
def []: (String) -> String
end
type String::encode_fallback = Hash[String, String] | Proc | Method | _ArefFromStringToString